I had noticed a while ago that he hadn't been posting so I decided to check on u/ThatsAlright to see if he was active on any other boards, and it says This user has deleted their account.
Despite disagreeing with his takes on many philosophical and economics topics, I did enjoy his posts. I hope he didn't finally become a good communist.
He was pretty distinctive, and I haven't noticed anyone taking the same positions he did, or arguing in quite the same way.