This is huge news. Basically steam is now acting as playonlinux/lutris and allowing you to launch games via WINE. But, valve haven't just done that, it turns out that they paid the DXVK developers which is why its progress has been so rapid and impressive. They have their own fork of WINE called proton that they're using in Steam.
https://steamcommunity.com/games/221410/announcements/detail/1696055855739350561
https://steamcommunity.com/games/221410/announcements/detail/1696055855739350561