The crux of the issue is, this part doesn't hold up.
There were a lot of people with very real and legitimate reasons to dislike 4E.
Just because YOU don't experience them doesn't mean they are made up.
It's not a matter of complaining about what you experience. Remember, the first salvos of the edition war were fired by h4ters like the Alexandrian before they'd had a chance to play the game, let alone figure out that the various ways we were accustomed to compensating for D&D's perennial issues were no longer all required.
There were legitimate criticism of 4e early on. Skill Challenges, for instance, were demonstrably messed up, there were some clearly broken power combos, that sort of thing.
They weren't really what the h4ters latched onto, though, because they kept getting fixed in updates.
The more typical h4ter rationalization - dissociative mechanics, fighters casting spells, and so forth - were either outright lies, or selectively-defined straw men that didn't hold up to scrutiny. They might ultimately be about something real - class balance, for instance (4e had it) - but they weren't legitimate.
I hear people make all kinds of complaints about 3E that NEVER happen at my table. This doesn't mean they don't happen for those people.
Sure. But, you can at least see /how/ they could happen, and how they might be difficult to compensate for. LFQW, for instance, was a real thing, mathematically demonstrable, and, while may 3e fans claimed not to notice it (or actively liked it), they couldn't argue that it was just being made up - the numbers those complaining cited were real, taken straight from the books, and they added up.
The few complaints of that nature about 4e (Skill Challenges, assumed attack and non-AC defense progression at Paragon & Epic, Elites/Solos and general 'monster math') were refined and fixed.
And, of course, there's speed of combat. 4e combats are more detailed, tend to involve more enemies, and give every player equal agency in contributing to the combat - meaning that relatively few players get virtually skipped over because their character has nothing useful to do or no meaningful choices to make or resolve. To some players that seems slow because, while you're getting more for the time you invest, it is kinda a large single block of time. To others, it seems slow because they're used to dominating play, and letting everyone else have equal time drags as they wait for their turn to come back around. And, to still others, the impression the combat is slow is simply because it's actually being resolved over several rounds, instead of in a surprise segment.
The remaining complaints - dissociative mechanics, fighters casting spells, and so forth - are, indeed, not at all legitimate or real. They may have a real agenda other than just reactionary nerdrage at the bottom of them - like balance, caster primacy, or realism - but the complaints themselves aren't about real things, just stalking horses for issues that the h4ter knows won't be taken seriously if expressed honestly.
What part of the "perfect storm" explains why anyone would play a game they don't like if this storm had not happened?
Well, it has happened with every other edition of D&D. They have fairly long runs, and new material for old editions was not generally forthcoming (due to little things like trademarks and copyright law), so even serious hold-outs would have little choice but to buy material for the old game and adapt it, and might well find it easier to just start playing the new one, instead. Especially as the new game has generally been better than the old, with each rev-roll, anyway.
