I am sure everybody read about Blizzard "Frat Boy" lawsuit by now and I'll give my 2 cents.
I believe WoW was a lighting-in-a-bottle that could not be reproduced. Top people working at WoW, be it skilled or not, pretty much lived from its momentum for decades.
Because the game graphics and gameplay were more or less set in stone, working on it was relatively easy. I believe networking, seniority, and office politics got more important than actual skill, innovation, and ingenuity but since WoW was still selling like hotcakes nobody complained.
The top got away with lots of stuff, and as the years go by this turned into a "culture". Part of the top got lazy, outdated, and arrogant but as long as WoW was selling, who could complain? Biggest MMORPG of the world amirite? Blizzard is probably doing something right. Until it was not...
Now WoW is a shadow of its former self. FF 14 exist, Fortnite exist, Genshin Impact exists. The top cabal still try to protect itself, but as members leave the company and sales numbers go down, the cracks on the wall start to be show and people start to question the leadership skill.
So we have WoW 2021 where a rotten core of dubious skill manned the titanic to the iceberg of failure. Some god-tier talent could fix WoW, but why a god-tier dev would want to work at an old-ass MMORPG with a bad story and dated graphics?
So this is why the guys on the lawsuit got away with murder for so much time. The game's success made them untouchable, and the game momentum made this success last for a long time. I believe there was a fear the guys at the top were game design demigods who could not be replaced and they had the numbers to back it up. Whoever at the top who was not part of the problem (or friends with them) was more interested in not disrupting the status quo as long as the sales were good.
The reality I believe WoW is not that hard of a game to keep going. I even dare to say the reason all expansion content is made to be disposable is the NEED to remake everything every expansion so they keep their jobs. I can see some top executive who knows nothing about games being afraid of firing someone on a lead position though, no matter which accusations.
I also suspect, perhaps, while not everybody literally pushed someone to suicide, they did not want a more strict job environment. Letting the Alex guy do his things may mean they could get away with lesser stuff. They did not want the company to turn into one of "those" places.
tl;dr - Past success made the old crew immune to criticism. People below them had no power, people above them were interested in the sale numbers, part of the problem, or friends with the guilty part.
Thanks for coming to my TED talk.