More recently, from Phoronix:
While the initial driver patches were merged to char/misc and now in turn within Linux 6.10 Git, much of the enablement work wasn't accepted in time. Thus for Linux 6.10 the new NTSYNC driver is marked as "broken", so it won't even be built for normal kernel builds.
Hopefully for Linux 6.11 or sometime soon the rest of the NTSYNC patches are upstreamed for yielding this massive boost to Windows games on Linux.
Support for it already seems to be there in wine, so rather than wait for 6.11 I think I'll just go ahead and apply the patches myself to 6.10-rc7 and see if it makes any difference to the one game I regularly play. If my computer blows up as a result I'll let y'all know.
(Result: None. The versions of wine I have probably need patching or at least configuring in order to use it. In the course of briefly considering trying to work out how to do that, I discovered that the expected improvements are not nearly as dramatic as were suggested compared to what's already most often done in proton (fsync). The main benefit for most of us will be better compatibility, not huge performance gains. Well at least my kernel is ready for it.)