I ordered a new BB a few hours ago to replace the Cane Creek Hellbender Neo with those fancy SKF bearings. CC discontinued selling bottom brackets with those bearings.
The bearings still spin, but it feels like you're trying to run in quicksand. No grinding or similar sounds you get from a conventional compromised bearing, just friction.
Can't remember where I saw it, but think those type of bearings are now being used for pivot bearings instead — which they're better suited for versus the constant rotation of a bottom bracket.