One thing I haven't seen tried in any of these things floating around (I'm still on macOS 15) that is the first thing I'd test after deletion is to stick a locked dummy file in there of the same name and see if that interferes with redownloads without any of the other mess. That's a classic simple hack. Ie, after deletion just a quick
# touch com_apple_MobileAsset_UAF_FM_GenerativeModels
# chflags schg com_apple_MobileAsset_UAF_FM_GenerativeModels
Then reenable SIP (or not). While maybe Apple stuck in some extra smarts in their download logic, and a full system update I think nowadays just blows everything away and replaces it, I've found in practice developers (not unreasonably) tend not to consider non-trivially-removable files appearing "where they're not supposed to be" and build a path for that. Granted, possible the process just ends up spinning trying to redownload over and over again or something but would be an easy thing to test.