In the end things like taking out non-working drivers in derivative builds is arguably more "lame" from a dev or preservation standpoint than "scorched earth". It's not going to slow development even if you can come up with a worst case scenario in your head where it does, and it's the same deal for the torrent crew going into the future. If those guys care enough to make separate split and merged torrents every release for the same roms I don't see a complete mame torrent of some type going away any time. That said, if I was personally designing an arcade only build I wouldn't take out nonworking drivers because the goal would/should still be to preserve all arcade data.