Henadic Theologian
Legend
That is possible.
I would, based on what Crawford and particularly Perkins have said, think that it's unlikely this was something they were told to do from above, but I can't rule it out. What probably did come from above was the sudden change in timeline, where they were saying "Oh yeah we're going to iterate a bunch" and then later "Yeah will give you bits of the DMG and MM to test", and then neither of those things really happened. But we know where the whole 70%-feedback-loop deal came from and that was Mike Mearls, and it was chosen specifically because Mearls wanted to get lapsed players back in and to keep them. I suspect were he still in charge he might have taken a different approach to 2024, and that Crawford/Perkins retained it because they didn't really know what else to do.
That's not the impression I've got from the actual 5E setting books. Like, VRGTR for example, the setting info is just rushed. It doesn't feel "slim and useful" to me, as much as "Holy hell we've got to cover a lot because we're only ever getting one book, so every single nation has to be covered, which means it's going to be real light for all of them because of the page count!".
The "somehow" is because it absolutely did happen in 2E, 3E, 4E, and with Eberron, 5E. That's er... quite a lot of decades and again Eberron shows it isn't an impossibility in 5E. I don't think anyone actually expects everything from every book, or even most things from most books to be covered - I've never seen that opinion from an actual poster, rather than attributed to nebulous "people" who don't actually exist. What people have expressed a desire for is books more similar to 2E/3E/5E Eberron in terms of the amount of setting info.
Also, I'd say it's worth noting that 5E Eberron probably supports a new DM coming to the setting rather better than say, 5E Planescape, or 5E Ravenloft.
I do think one of the problems is that WotC are doing "one book and done" for settings that were never intended to operate that way. Especially as WotC has reduced the page counts compared to earlier releases, and insisted on including increasingly large adventures and bestiaries in the setting books (despite increasing the price by far more than inflation).
It didn't help that a good chunk of the book was devoted towards stuff like how to do your own domains, leaving less space for the rest.