I don't think there is a lack of interactions with zelda its more of a lack of engagement which isn't unique to her. ivy, samus, snake, to a certain extent even jiggs and marth want to avoid engagements. Zelda's interactions are just a different type of interaction. interaction is more how you influence something whether its direct or indirect. Engagement is more about staying directly involved. Zelda gives you plenty to interact with but doesn't engage which is what a zoner/range fighter does.
I categorize zelda as a passive aggressive fighter. And people hate passive aggressive things like a backhanded compliment. for instance Passive aggressive people don't want to be in the heat of things but they don't want to be ignored either. You hear and recognize a backhanded compliment from this person you can't be really be insulted by it but you can't be fully accepting of it either. You have to choose how to react to it. you could get angry and freak out or you can try and understand what the other person is really trying to say and why they said it.
You see the din on the field but you get to choose what should be done about it. The way to beat her passive aggressive nature is understanding her underlying motives. does she want me to jump, roll, block, attack? Zelda makes you choose that's her interaction. TLDR The opponents interaction should be predictive not reflexive so they can engage her.
That was just about design and her design is great to me. When i loose to her, and i really only loose to Zhime's zelda, its because i made a mistake not because i couldn't get to her.
Her kicks and what not are no worse than a falcon knee when you consider how fast falcon can put that knee just about anywhere in a split second.
I'll go through this slightly out of order:
1. I agree with you that other characters want to mitigate interaction from the opponent. That's what dashdancing is all about, for example. However, once you get most of those characters in a bad position, it is relatively easy to keep them in a bad position to extend your punishment game. This is not the case with Zelda and Jigglypuff. Once you get them in a bad position, it is substantially harder to keep them there, and the punishment game is extremely nullified. I have an issue with Zelda's neutral game, which I'll get to, but I don't mind her as a ranged fighter. This seems to be the core of your argument, and I largely agree with most of what you are saying concerning how she should play out.
2. Ideally, you want to balance interaction among the cast in a way that is normalized. You start with a set of rules, put some interactions to those rules, and then add deviations. Zelda's kick is not "okay" because CF has a knee. That's a faulty way to go about it. Similarly, Zelda's ability to negate punishment games is not justified by Jigglypuff having a similar attribute. Those qualities are degenerate to the point that those characters are polarized towards them. We should not go out of our way to repeat things like Fox's upsmash, for example. And while these things are borderline acceptable for this game, we should be trying to avoid making more polarized instances of this problem.
When other players tell you that they don't like Nayru's, what they're actually saying is "I don't like having a large portion of my punishment game nullified when I feel like I should have you" - and by all rights they would have any other character. Even Jigglypuff has to adhere to the opponent's positioning options when she's been put into a bad position. When I played Zhime, I said "this move is stupid I can't punish you with anything but clean combos", to which he said "then combo better". This is a flawed perspective because every other character in the game is susceptible to more punishment from "dirty" combos based or re-engagements from positional advantage or juggling (they're very similar honestly). Zelda does not do this. Zelda can use combo DI to get away from the opponent to always keep Nayru's live as an escape option. As the opponent, you can't chaingrab her, you can't re-engage her over and over with positional advantage, you can't really juggle her past a couple hits, and her combo weight is already naturally combo-resilient so clean combos are extremely limited at best. Anything that's close to a true combo risks eating a 50/50 since Nayru's from a poor position can let her convert on you right back. You ever combo a falco player and mid-combo he shines you out of it and combos you back for like 60%? Zelda does that in the air, with more range, more invincibility, and she's MUCH more resilient to punishment than falco is. Your best option for beating her is to hit her with strong attacks from neutral over and over, but the character is almost strictly designed to deal with that from neutral too. This is not normalized interaction. And it's all based on
one move. I understand why everyone else hates it and I agree with them. Having a few mediocre ways to not lose to it does not make it acceptable.
3. Predictive play is not a good way to play a smash game. Predictive play is essentially putting yourself into a position where you think you can outplay the opponent regularly. It is much better to retain your options and to choose the best option when it is suitable for you to do so (reactive play). Playing predictive is bad, bad, news against a character that is perfectly okay trading 50/50 with you like Zelda is. If predictive play is your recommended way to fight her, that in itself is already problematic.
I'll try to summarize why I personally think Zelda has a poor design:
- Polarity towards camping. I don't mind Zelda's playstyle as a defensive character, but she is too polarized towards that, IMO. I think her offensive options should be improved. Right now, every match with a Zelda in it is Zelda camps you and you camp her and the first one to stop camping loses. Having a character where every single MU she has becomes about both players camping is a huge red flag. Giving her some offensive options while reducing her defenses should fix this by normalizing her character.
- Inability to punish properly. Nayru's is just a problematic move and that's all there is to it. I also think that the coming out of up B hit should not send a hit opponent into aerial tumble at 0%. This makes it way unnecessarily hard to edge guard a character that already has a fantastic recovery. She can keep the recovery, but the opponents should also have the ability to cover her options to some degree rather than guessing. This should normalize her recovery. Nayru's is just absurd and really needs to be examined.
- Her punishment game. While not addressed by your post, I dislike that she has 3 kick hitboxes. The dual strong kick only has 3 outcomes:
1. The super kick is too hard to land, and the move feels underwhelming.
2. The super kick is too easy to land, and the move feels absurd.
3. The super kick is just difficult enough to land, where sometimes you get it and sometimes you don't, and the move feels like it has unnecessary variance.
I think the kick should just go back to the simplified version where it's either strong or weak, and kills at 90, rather than sometimes killing at 60 and other times killing at 110. I also dislike that her entire character is crouch proof and functionally safe on shield, but I'm not sure that those are truly problematic so it's just something to note and go back to later. I don't think it needs to be addressed right now.
- Unnecessary complexity. I think that Zelda and Snake essentially force you to re-learn how to play the game when you're playing against them. Not having principles and a unified method of how to interact against these opponents is hugely detrimental. I agree with the idea that the player should have to learn the match-up to be successful, but these two characters push that idea way too far. I think normalizing her with the above ideas will go a long way to making Zelda behave like the other characters in the cast and should solve this issue on its own.