To be fair, if someone is still sticking around with WoW at this point, there's a decent chance one will play the game no matter what Blizz does. Not to say that's everyone, but Blizz probably found their player floor around Shadowlands... i.e. we can use and abuse X amount of players and they'll never leave. I tend to all it institutionalization, but programming works too.
The "you don't need it" argument has never held water. If we want to get really technical, that line of logic would imply that almost all mythic raiders don't need mythic gear because "world first raiders can clear raids with mostly heroic ilvl gear, so anyone who can't obviously needs to git gud!" The counter would be that non-world first raiders need the gear as a crutch, which then undermines the usual line of "you don't need it" as increasing ilvl is basically the only crutch one has now to beat content. Ultimately, the "you don't need it" argument stems from a certain strain of elitism that's been fostered by the design of the game; yes it'll exist anywhere, but WoW has been designed in a way that gear promotes such thinking.
Imagine if the following change was made to the game: all gear ilvl caps at heroic raid level while mythic raids are designed around everyone having full heroic ilvl gear equipped. Suddenly, gear progression has a much more broadly attainable end point for many players, and mythic raiding is suddenly completely about skill and not gear disparity (it basically becomes the Mage Tower but for raiding, rewarding non-power gain items/cosmetics). People would suddenly find the irony that the top end mythic raiders would probably be more than fine with this (as well as the vast majority of players), and the people screaming the loudest about "this gear isn't for you, git gud if you want it" would probably be the most irate with such a change. While I'd love for such a change to occur, I think Blizz would be terrified of such a change as they'd probably find out that a good portion of mythic raiders probably don't want to be there as they're only chasing ilvl and gear power while not giving a toss about mythic raiding in general... a further irony would be that it mythic raiding would be more accessible than ever but would simultaneously see a large drop off in participation in all likelihood.