They made no PR faux pas here. I am commonly skeptical of Blizzard and have the unsubscribe rate to prove it.
This is people making things up in contradiction of both statements and evidence. The only way shrinkflation would make sense is if they hadn’t hired an entire 200 person studio which would roughly increase their WoW team size by 50%. That roughly corresponds to a 50% increase in content release speed or a 33% decrease in content release time elapsed.
Now, can people be skeptical new studio will do the job well? Sure! That’s a lot of new people to onboard and other devs have struggled with such moves. That would be a reasonable concern. But you don’t increase your employee overhead by 50% to move 50% faster with the goal of also reducing the depth of the content. That’s a wash on the side of more liability and complexity, and at odds with pennywise pound foolish behavior that’s being feared here.