There are already independent benchmarks from real gamers that tested games with Denuvo and when it got patched out. Guess what, Denuvo causes massive performance issues and bloated the size of the game.
I bet those "independent" benchmarks are cherry picked with exactly a specific hardware especially optimized for it with the help from Denuvo developers.
DirectX 11 and 12 don't exist on Linux (TF2 also only uses DirectX 9 on Windows). Anyway, not only TF2 is effected but other not well maintained Source games too. The culprit is the newest version of LLVM (and another package I can't remember the name of, but it's a popular one that is always the problem) and that was two months ago (joys of a rolling distro). This problem can only be fixed by that one guy at Valve who still works at TF2 to adjust to the new LLVM.
Edit: it can also be fixed by the package maintainers by reversing that oopsi
Every Anti-Cheat that works on Linux (the big one for example EAC and Battleye) only has surface level access and can't scan your whole PC or act like a rootkit like on shitty Windows. Anything that goes deeper isn't possible without root permissions and that doesn't happen on its own with a normal Linux installation.
This FaceIT "Anti-Cheat" has other problems why it should be avoided.