Could basically change this to the other two have exclusive games. Microsoft don't seem to like making many serious attempts at those lately.
Anyway I'll say Switch because it's the one I'm more interested in having. Might pick up a used PS4 sometime in the next year but 99% of the reason is I want to play Bloodborne. There's other stuff I might like on there, but not many that I couldn't live without playing someday. The Switch I like more for it's handheld capabilities than anything else.