PC pretty much all digital, PS4 pretty much all physical, switch depends, if its cheap enough or going to get a lot of playtime (multiplayer, massive replay value etc.) and I know I will enjoy it I go digital, otherwise I go physical.
Steam makes digital pretty much the only option, PS4 I don't mind going physical since most games I get for the PS4 get a single playthrough but I try to go digital with switch when I can since it aids the portability so much