The TF2 64-bit update has landed
Open link in next tab
https://www.teamfortress.com/post.php?id=220436
https://www.teamfortress.com/post.php?id=220436
They could have compiled the game for Mac using the same techniques used for this update. The likelihood that Valve will recompile any of their games for Mac seems very low though.
They already have the tooling needed to compile old source games to render via Vulkan but I don’t think they’ve created an equivalent for Metal.