Win10 only supports this in specific high-sec enterprise configurations and, as indicated, Microsoft will not be porting that back to Windows 10. One can reasonably expect that Windows 10 support will be killed in favor of this new API, specifically because it means game studios can stop paying for soon-irrelevant development effort into Windows anti-modding. And I bet TF2 starts blocking unattested (and, so, Windows 10) players within one year of Valve enabling the new attestation API on Steam hardware in Windows/Linux.

Linux is and has for years been capable of supporting all of this at any time, and when-not-if Valve enables attestation of a clean sealed-booted Steam Linux environment for their hardware, AAA multiplayer games will begin allowing only sealed-attested Steam Linux players to join multiplayer games from Linux.

Microsoft isn’t doing this to screw Linux. Microsoft is doing this to avoid losing the secured PC gaming market to Valve. They already lost the (secured) console gaming market, after all.