Which gives some credence to the idea of what went wrong with 4E. Designers may have figured all the traditionalists flew the coup.
I think it was a mess of different things, including that.
In fairness, I truly think that they were trying to
design the best game possible. But that was the problem. You had very good designers (such as Heinsoo and Mearls) who had very strong opinions on what design should be. They also believed that people were all "up-to-date" with the game - in other words, 4e was a "natural evolution" from late-stage 3.5e. Heck, you had Mearls, just prior to joining WoTC, write that post in defense of miniatures where he introduced the whole (I am not going to use the phrase...) "MMI" into discourse.
The problem was that the playerbase, largely, wasn't ready for it. There were still a lot of people who played some (or all) ToTM. You were cutting out the OSR people completely (and hyperaccelerating that trend). Most players weren't playing with Book Of Nine Swords, so the changes were a complete shock. Not to mention that the game was going to be unfamiliar- unlike 5e, which attracted back a lot of the parents who had previously played.
Most importantly, they misread the appetite for a complete rules do-over. 3e was able to do it because the TSR line (which was inter-operable and unchanged for 25 years) desperately needed a complete refresh and there was a consensus in the community that D&D was in a lot of trouble. The community was fully on-board. But 4e came out
when 3e had just been released and people had spent all this money on it. There was no driving desire for another complete re-vamp.
Combine that with moving so hard against legacy components, and it was going to struggle.