Looking at the platform totals, looks like PS3 in Europe is the next milestone for Switch.then shortly thereafter PS1.
So still some more wins left to come. If I had to guess, I'd say it will make it to #3 in NA and worldwide, #5 in Europe, and #1 in Japan.
Bet with Liquidlaser: I say PS5 and Xbox Series will sell more than 56 million combined by the end of 2023. (And over 130 million lifetime)