There’s absolutely no reason to expose people for cheating in a video game. They aren’t doing any genuine harm to people. It sucks to deal with a cheater but it’s the most tame wrong doing anyone can do in this game.
There are community resources on third party sites that some Roleplay realms use to keep track of genuine abusers, creeps and racists because many of them put the work in to keep abusing people and it seems no amount of bans or actions have ever stopped them. I think that’s fine, even great, for a community to do if they so choose, nothing for Blizzard to be doing.
As for the cheaters and others who do more serious things, I would hope Blizzard can find a way to permanently ban most of them. It’s a real issue when the only course of action a community feels it has to dedicate their time and energy to protecting others from very well known abusers, tracking them because whatever Blizzard does or can do simply isn’t enough.