If it crashes when launching the game:
https://github.com/ValveSoftware/Source-1-Games/issues/5043
Tl;dr; Use the Flatpak or replace libtcmalloc_minimal.so.4
cd "~/.local/share/Steam/steamapps/common/Team Fortress 2/bin/"
rm libtcmalloc_minimal.so.4
ln -s /usr/lib/libtcmalloc_minimal.so.4 ./
If it crashes on VSH maps:
https://github.com/ValveSoftware/Source-1-Games/issues/5044
Unfortunately, there is no known fix.