If all they are doing is wokifying 5e, why will it take them 2 and 1/2 years to do so?
You have to read between the lines in their announcement which a lot of people miss:
They've begun work on new versions of the core rulebooks. Recent surveys tie into that.
The recent surveys asked a LOT of questions about
Classes, Class abilities, and Subclasses.And they are going to do more surveys:
...but expect more surveys. More will be said next year.
If the surveys next year continue to ask a lot of questions about Classes, Class abilities, and Subclasses. Then we have less and less reasons to not expect a full 5.5 style revision.
I expect that the game will look visually the same, but that there will be a lot of "small" mechanical changes in the class structures...
They will totally get away with this because unlike 3.0's 3 year run, 5e will have been the longest running WotC edition when 2024 rolls around.
They will absolutely refuse to call it a new edition, revision, or 5.x anything. Ever.
They 50th celebration of D&D will give them a lot of cover in the form of general good will, and positive press for the D&D brand.
The special 50AE D&D not-edition could not have the ground better laid with sugary sweetness to help the people pretend that it isn't totally a 5.5 revised edition with a smile.
...
They have absolutely no incentive to hire more writers or make more content than the glacial pace they've set thus far ...
IMHO, their release schedule is one of the few things that they actually did right.
There is just no need for tons of splat books. But IMHO they did fall short in providing real options for GM who might want to go into domain play etc,. But that is probably a result of the decisions made with their core books.
Aside from that, while I imagine their MtG setting books sold rather well, IMHO no one really plays those setting very much - they benefit a ton with collector tie in and the MtG crowd has never mixed with the D&D crowd to the extent that WotC would like. And they never will.
So for me it was not so much about their release pace - it was the types of books that they chose to release...
...
The soul of the game and identity of D&D has been dying ever since it was taken out of the control of people actually involved in the hobby and sold to megacorp.
This has been true since Gygax lost control. For all his business failings, he at least had a personal stake in what the game meant to people. This effect was mitigated a great deal in the Williams era of TSR because a lot of employees who worked under Gygax still had input into the game.
Things just got accelerated with WotCs 3.0, and they are ticking along even faster now that anyone with a real love for TSR D&D is now off of the WotC dev team.