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
I recommend switching over to the myr* links in the r/roms mega for the time being.
I also recommend buying a 4TB hard drive and grabbing anything you think you'd plausibly play or care about.
Tooling around these takedowns seems to be rapidly getting "better" and it wouldn't surprise me to find out initiatives like this getting increased funding as they're a way to deploy AI to make it look like you're meaningfully doing something to "protect" revenue
I believe the "perfect" use case for these tools would be hentai sites considering just how much porn of copyrighted characters there is. Like it'd take years to manually copyright strike hundreds of thousands of smutty Samus or Link .jpgs but an AI could probably do it in a few days