I mean, I think, it’s more “fun” for them, if they can closely walk the line of what’s acceptable and what not, and really make the moderators think hard, if they should ban them or not.

Really, your advocacy for more diligence when banning will straight-up increase the work that a moderator has to put into such trolls and therefore increase the potential for trolling.

If on the other hand, a moderator pro-actively bans people that try to state risky things and that test the boundaries, then they have very little work and they don’t get trolled, because they just click one button. The person re-creating their account and trying again and again, would be trolling themselves, because they create a lot of work for themselves, but not for the moderators.