Blizzard did the same exact thing with Diablo 4 too, and D3 also famously sucked at release.

You'd think they would have learned by now, as they repeat the same exact mistakes over and over again. It's like they hate their playerbase.

The biggest problem I remember from D3 release was that they listened too much to the "this is way too easy, not hard like D2 was" from the beta feedback. Inferno difficulty was absolutely ridiculous. I know people also were unhappy about the AH, alleging that the item drop rates were lowered to drive people to use the AH, but I don't know whether or not that was true.