PC, then I keep thinking about getting a Xbox 1X then I remember I have 2 PC's and a Shield TV and emulation... Really it's what games you want to play, the PS4 might have some exclusive you need or the Switch or the Xbox or the PC...
If your rich buy them all, it's the only way to get all the good games sadly. Short of that your only option is to place your bet on what you think will have the games you desire.
TLDR: I am old and like old games so PC is best for me.