Where can I read about why only some drives can rip, and how AACS for UHD is different that HD?

[2938xy29r]

I've read how AACS works plenty of times, but all the papers and forum posts basically say that's how it works for ALL bluray disks. There is clearly a difference because SGX is only needed for UHD decryption code and even Pioneer drives can rip the HD disk of a v66 bluray set.

I have Scarface which is AACS V66 and HD disk rips easily even with a Pioneer drive. UHD needs SGX and for some reason even cheap USB Pioneer UHD drives don't look to ever be supported..

[Woodstock]

Bluray (regular) uses AACS version 1, with sub versions each time they try to revoke player keys. It's mostly broken, as far as being effective against ripping programs.

UHD goes with AACS version 2, with similar sub versions as BD, but not quite as broken for ripping - it still needs key file updates as new disks are released, and drives that won't block efforts to read them (UHD-friendly). Any drive built prior to late 2015 cannot read UHD disks due to hardware limitations.

AACS 2.1 is in the wild, but rarely used. It tries to embed information about the ripping machine into the video data, but it can be defeated.

[2938xy29r]

On my Scarface copy MakeMkv reports "v66" for the HD disk too.

I was also wondering with all the cache and RAM vulnerabilities in x86 CPUs why nobody has not just dumped PowerDVD SGX enclave to defeat newer AACS without having to touch drive chips?