Again, I only intend a civil discussion for progression. If you don't intent to follow these guidelines (you should be anywhere, really) then please leave this discussion immediately.
I understand you have a certain perception of 'elitists' as some people do tend to get an attitude after they start getting more skilled than other players, however, you should be aware that there's the same stereotype for newcomers who get salty and blame character design rather than ask politely for advice on how to deal with certain things or attempt to figure them out themselves. Both the noob and elitist stereotypes have some truth to the behavior's they describe, but I feel that just putting someone in a box(either by name calling or identifying one bad behavior and attributing all the rest of the stereotypical ones) is a sort of low-effort low-reward way of making a point. Thus, i'm only going to discuss individual points as i think it will be more constructive.
" It has some invincibility frames at the start meaning attacking players are in for a serious punish if they get hit" aside from the obvious leap in logic than invincibility frames at the start of a move mean a 'serious punish', just distinguish between grounded and aerial nayrus, only the grounded one has invincibility and it has around 50 frames of endlag after the hitboxes end and she doesn't get much off of the grounded hit anyways. Aerial nayrus starts a good punish for zelda, but only because of the land cancel on it, which she can only use effectively from certain heights. This effectively means, and you'll just have to take my word for it, that she has to get a read on you in order to start a combo with it and it is not in fact something that she throws out whenever as a panic thing and then zero to deaths you because of it.
"I find this mechanic unfair for heavy characters like Fox" in smash there's actually weight (how heavy or light you are which affects how far you fly when struck by a horizontal trajectory as well the amount of total kb you take) and gravity (how quickly you start to fall after being knocked upwards, which affects how high you go when knocked vertically). Fox is light, but he has high gravity so even though he suffers a lot of knock back in general, if it's a vertical sending move he starts falling while he's still in hitstun. When you say "heavy characters like fox" it's confusing a few different qualities.
"because missing the hit means you'll get hit.... and probably end up dead..." That's generally what happens in smash bros though, especially fox. Understandably not fun if you die from most mistakes, but you can always choose a character that this happens to less.
" you get sucked into her special attack and probably end up dead because of her incredible range and power....
why they think this mechanic, the free invincibility frames, is fair ... .... and baiting Zelda can be tricky because her range is well equipped to handle baits like Fox's lasers." All of these really give off the impression that you're saying these are too good for Zelda to have. Zelda is a pretty contentious character and not everyone agrees on how comparitively powerful her tools really are with the rest of the cast or how she would fare if you nerfed her further. Most zelda main's are more than happy to discuss her character design civilly, but just be aware that if you betray a tone that suggests you've already made up your mind about something you're sort of asking for a fight when people inevitably disagree with your assertions.
"why they think this mechanic..." 'why's nearly always sound judgemental in an argument because they usually are. This is pointing a finger at anyone who disagrees with the assertion that zelda is unfair and only makes those people feel defensive. My advice on this is, we're all adults here, more or less, and can take a little arguing, just if you come into a thread guns blazing, don't be so shocked when you get shot.
