For those unaware, the linux version of TF2 is still 32bit, and runs on ToGL - a DirectX to OpenGL translation layer.
A few days ago, Valve published a TF2 private branch called “x64_linux_test”: https://steamdb.info/changelist/21975149/
Then a few hours ago, Valve update TF2’s “App Config” to include references to x64 Vulkan TF2: https://steamdb.info/changelist/22010846/
Looks like it’s coming soon, in theory should bring some nice performance improvements. But “soon” in Valve Time is… who knows
Edit: the beta is live
It is to make the game bootable in the first place, you have to swap *.so files to launch the game as of today