Interestingly, this rash of DMCA takedown requests is apparently related to the Garry's Mod DMCA strikes from a while back. Apparently, copyright protection companies have started using some kind of automated AI service to mass flag and DMCA hosters of infringing material. This is why it's all so haphazard and the emails full of spelling errors
Any word of how successful they are at targeting private trackers this way? Could that be an answer?