My impression from playing games is that bugs don't kill the games, stopping feature releases to fix bugs kills games. Everyone just laughs at the bugs, even when they change the outcome of an esports matchup with millions of dollars on the line. In the end, the players keep playing and the sponsors keep buying ads, so it's no biggie.

Looking through Blizzard's tech talks about Overwatch (they do exist!) is that they focus their testing on making the game fun. They do not say that this comes at the expense of thorough unit and integration tests, but from playing the game, my impression is that it does. Sometimes a patch will come out and the patch notes will be along the lines of "that ability didn't actually work in the last release, but hey we fixed it". Unit tests always notice abilities not working; playtests don't always pick them up. But unit tests will never make your game fun, and nobody will play a game that's not fun. So I'm guessing they don't work on that.

(This video shows what happens when you uncover a lot of untested corner cases all at once: https://www.youtube.com/watch?v=hl11iqagWIc)

There are many software engineers that do enjoy bug-free software. Nobody cares because people are given passes time and again for bad software. Some bugs in a game? "OMEGALUL". Some credit card numbers stolen? "Oh, we're deeply sorry." The software crashes the plane from time to time? "Hey, we'll fix that in the 737 MAX v2." If engineers working on safety systems don't really care about bugs, why should a game whose competitors don't care either? It's just throwing money away. When Dota2 starts stealing LoL users because of their amazing bug-free client, then suddenly everyone will be working on testing frameworks. Until then, I expect some bugs in my games.