Lichess (a popular chess site) combats this issue by not actually banning cheaters. Instead, the cheater is not notified that they were caught and is still able play or create games, but they're only matched to other cheaters.
A bunch of video games do this ('shadow banning / shadow pooling') - with varying degrees of success. A lot of the cheaters still just create new accounts every so often.
Technically they get a warning label that they use computer assistance (dunno if they themselves can see this or not). Players can still play them if they choose. They just open new accounts though.
