Thanks for your thoughtful reply.
I think a big difference to me is in how she's rewarded. In Brawl, the reward was damage. Approaching ZSS wrong /hurt./ In Ultimate, it's like, oh she reset to neutral and wasted my time. Maybe you ate a baby paralyzer which MAYBE (depending on positioning) set up for a throw/dash attack/nair mixup. Ultimate ZSS does her damage by finding a way to hit you. In Brawl she got her damage by messing with you while you tried to hit her. She's running away but she's doing so in service of finding opportunities to nair you vs. running away in order to bait you into getting stunned/whipped.
I see what you're saying, but I still disagree.
ZSS still has one of the craziest advantage states in the game, so that hasn't really changed. Approaching ZSS wrong hurts in this game too.
As for how they play the neutral, Brawl ZSS lived in a world where even the fastest of hitboxes were getting punished with a buffering system that rewarded your reaction time. ZSS side-b and grab were regularly getting avoided, and after an initial rise to top tier post-Apex2012, perceptions of ZSS fell off pretty harshly (she never won a big tournament again).
Brawl was also a game of intense microspacing, not like the set-distance dashing we have in this game.
Meta Knight f-tilts were regularly getting punished by pristine spaced d-tilts in the ditto.
In that environment, ZSS
had to play that defensively, because her hitboxes weren't good enough for anything else.
No one's hitboxes really were good enough for anything else, to be fair, besides Nairo's Meta Knight (which, if I had to guess, would have paved the way for lots of similarly aggressive styles if the game had any kind of future, but since the game didn't continue that didn't happen).
On the note of Nairo, it's worth mentioning that there was also a very distinctly human element in the mix here--Salem pioneered Brawl ZSS neutral, and Salem, as we all know, loves defensive neutral.
Nairo, on the other hand, pioneered the neutral for S4 ZSS, and it looks very very grab-read-heavy as a consequence. If you watch Marss' S4 ZSS, you'll notice that it looks absolutely nothing like Nairo's--way fewer grab reads and way more empty jump movements, like you see with Marss' Ultimate ZSS.
Marss' style of ZSS in S4 was sub-optimal, but ZSS in the transition lost many of the the tools that favored Nairo's style and gained a bunch of tools that favored Marss' style. Had Nairo not existed in S4, you likely would have thought of S4 ZSS quite differently from the current grab-centric up-air up-b fiend that you likely picture in your head, although you'd also probably think of her as a bit worse, too.
Ultimate ZSS' hitboxes are overall better, but, just like S4 ZSS before her and Brawl ZSS before her, she still can't space them that easily (besides z-air) in neutral. At this point it's clearly an explicit design decision. Because she doesn't have a tomahawk option, it's very easy to anti-air ZSS, and once you, as the ZSS player, start getting anti-aired out of shield, you have to start playing grounded.
Grounded ZSS gets almost all of her reward from tech chases (meaning that nothing is guaranteed), and those start almost exclusively from grab whiff punishes. It's no coincidence that they gave ZSS the best initial dash in the game going into Ultimate--her ability to dash back out of your midrange burst range and then grab you for using that option is almost unparalleled.
Then, once she starts getting tech chases from grabbing, the opponent is going to start choosing options like dash in -> jump aerial to catch her dash back. This opens up the opponent for getting hit by n-airs, z-airs, and up-airs and the reward that we all know ZSS for.
The full picture is that ZSS is playing a grounded whiff punishing game to condition you into letting her play an air spacing game. It's like she switches from Sheik to Marth and back from Marth to Sheik when she's playing neutral. No other character really has this design, even others with tethers capable of whiff punishing (e.g., Samus, who bases her neutral on Charge Shot mixups and anti-airs).
The ZSS that you describe sounds more like a traditional zoner like Ultimate Pacman (baiting you into getting hit by fruit, in this case, which can lead to obscene reward). The items were the most unique thing about the character, at least from my perspective. Getting half a stock or a full stock from the items at the start of the match allowed ZSS to threaten a time win condition for the rest of the game. Very few of her matches ever went to time, though, since an opponent down by an entire stock was forced into approaching and usually getting annihilated as a result, since approaching in Brawl was so hard.
Overall, I definitely like the current iteration of ZSS best of all, and I think she's one of the most unique and well-made characters that the franchise has ever seen. It's the sole reason that I played her for about a year.
