We do mandate safety in general. (Probably less so in some countries than others.) So you mostly can't choose to fly an airline that defers maintenance to cut costs.

Presumably the consequence of regulators making canceling and delaying flights expensive is that airlines pay more to reduce the likelihood of that happening and fares go up as a result.

Whether that's good or bad is a matter of perspective I guess. Regulators could implement a lot of rules that would make flying more pleasant. But prices would go up.