I mean for as much shit as people gave D3 when it came out it's almost a decade old at this point, Blizzard hasn't put effort into it in years, and people still flock to it every few months for a new season. So even when they get pretty much universal shit from the vocal parts of the community they still have the classic Blizzard longevity. The only notable exception is WarCraft 3 Reforged and that was honestly more that their marketing was complete shit because people didn't understand what they were getting. Aside from a lack of ranked ladder the game itself was fine if a little buggy. That's not really new though, original SC / WC3 were absolutely buggy broken messes on release and weren't fixed until a paid expansion and several patches so eh.
Blizzard is still Blizzard and while I would love to give them a free pass and blame Activision or whatever else, they're still Blizzard. They have some really good employee retention, surprisingly, it's very rare to see people go 10/15/20 years in a company like we saw in Blizzard in this industry. If anything they probably need a lot of new talent because the rest of the industry has really stepped up. A small indie company in New Zealand made Path of Exile for example. Normally more competition would be a good thing, but since Blizzard is a pretty complacent company that isn't great at innovation (They usually copy trends instead of starting their own) all competition has really done is highlight the flaws that have always been there in Blizzard.
That said, I personally think Shadowlands is one of the worst iterations of WoW that they've ever done. It seemed great at the start but it became apparent pretty quickly that the reward system was unrewarding and unsatisfying. I see they're fixing it, but I'll take another look at the game for the next major raid, MAYBE. FWIW this is the first time since the inception of Mythic raiding that I've quit before I finished a tier and it's the first time that logging in and doing progression content ever felt like a chore.