Steam just got an upgrade that automagically runs a lot of games via a modified version of wine (called proton) sometimes even with better performance than on Windows. It's worked very well for everything I have tried it with so far. So that just leaves games not available in Steam. The biggest of which has to be Blizzard, however a lot of their games already worked decently well with Wine, so hopefully proton works with them as well.
As of today most games may actually already run better on Linux than on Windows.