It's blocked from Wayback Machine so I can't even check to see what was on there that caused it to get de-indexed.
What are your plans for this domain? I'd say it's going to be a big uphill battle if you're trying to rank it for organic traffic.
I'm assuming you're interested in it because of the backlink profile (If that's not the case, please disregard the rest of this post), because it has some very nice links but it's also got plenty of spammy ones, and there's no guarantee that the nice links will carry over any benefit.
If you're able to rebuild the site, appeal the DMCA takedown to Google by saying you're a new owner and it's a new project and all of the offending content has been removed, then that's just more reason for Google to ignore the backlinks.
If you're buying this to rebuild so you can sell guest posts or use it as a PBN - same problem as above.
It's possible that the domain dropped at some point, and was used for torrents or something like that, then got deindexed.
If I'm buying a domain for SEO purposes (Which can be incredibly lucrative despite how often domainers will whine about "bad names" selling for high prices...), the first thing I check is if it's indexed.
If it's not indexed, that's a hard pass from me. There are about a dozen other things I check for, but that's always the first one.
If I'm buying a domain with backlinks, it's because it can be like pushing a boulder down a hill. Buying a fresh domain with no history is like pushing a boulder on a flat road. Buying an seo domain with a sketchy history is like trying to push a boulder up a hill.