Your AVX statements are out of date. Nowadays AMD supports AVX-512 but Intel removed support from the consumer line (only workstation and enterprise products support it for the last 2+ generations)
Because Stardust said "Get a Steam Deck and then you'll see why" which makes no sense in the context of Denuvo DRM, hence it is most likely Stardust confusing anti cheat issues for DRM ones. Not that hard to figure out.
What? YouTube music is professionally sourced music like any other major service. You can upload your own music for personal use, but included music comes from the publishers.
As a father I can confirm this seems right