Essentially raid lockouts in their current iteration and form are what deter quite a few from wanting to raid. It flat out just does not feel good. We want the ability to re-clear content to play around bad RNG and so we can play at our own pace. The demand for deterministic loot exists because of the poor implementation of timegate. This is one of the reasons why mythic+ has so much more engagement.
No, as suggested elsewhere, they improve it while still keeping a form of timegate.
IIRC they tried a poor implementation of this in season 1, where they blocked off m+ and raids entirely instead of capping the ilvl of loot on a timegate from said content directly.
I also think the social aspect hard carried wow despite the subpar timegate systems design, not because of it.