I apologize if this is long winded, but I've been thinking about this stat block thing for a while and feel it's a symptom of a larger problem at WOTC. I don't think they really know who their audience is.
Way back in 2014, WOTC released 5e based on a not so great reaction to 4e (and the resulting loss of market share). Player feedback led them to create a game with much simpler mechanics then 4e. At the same time (by blind luck), streaming content begins to take off. So here's WOTC with a known IP and with a ruleset that is easy to use and easy to understand. The result, 5e takes off on streaming.
At the same time WOTC uses a licensing model to distribute content digitally (either as a pseudo-pdf equivalent on D&D beyond or as a VTT with Roll20 and Fantasy Grounds). So now they have streaming and multiple revenue streams through licensing that enable on-line and streaming play.
Then 2020 happens.
So, WOTC, through luck has positioned themselves to enable on-line play with minimum expenditure of resources on their part. Sure, they are developing content, but platform maintenance, billing, and customer service are all being serviced by the license holder. Better yet in addition to the revenue stream generated by the license, they're taking in revenue from purchases of WOTC content on the licensees platform. So, low overhead and lots of cash coming in.
This whole time, the player base is exploding. These new players (and some old) start looking at some aspects of D&D content and have issues with how race and culture are portrayed. Feeling a need to be response to the player base WOTC begins the process of making changes to what race means from a mechanics standpoint and changing lore.
So here's where I think WOTC made their first incorrect assumption about who their player base is. Historically, a majority of D&D books went to individuals who never used them for the purpose of play. I was one of those way back during 2e. However, I would argue that with the rise of streaming, VTTs, and COVID that these customers are dinosaurs. If they're not completely extinct, they are not long to the world. It's easier than ever now to find a game. In the content re-write, I think WOTC missed an opportunity to service the current customer. Think how great it would have been if rater than re-writing lore, WOTC just deleted it all and replaced it with instructions as to how to run a monster to achieve their determined CR score. To run your game, do you really care what spider god an elf worshiped to give a +2 to deception? Or would you rather have a monster stat block that had explanations of how to maximize the monsters play potential like that supplied by Keith Ammann?
As for stat blocks, are they really too complicated. I look at D&D beyond and the VTTs and I see that its pretty easy to navigate even extremely long stat blocks. On top of this, understanding that in a typical encounter a monster will take between 3-6 rounds of actions its not hard to plan out what they'll use in an encounter. (Wouldn't it be great if WOTC supplied instruction as to what a monster would do in an encounter!) I really don't think the modern player, who has all these resources in front of them is intimidated by long stat blocks. As further evidence of this, Matt Coville just ran a kickstarter that makes stat blocks more complex and it made 2 million dollars.
So the TLDR version. WOTC doesn't know it's player base, is misreading what the problems with the game are, and aren't making changes that will make the game better.
At least there's always third party content!