Yes but in November 2015, it had no competition and won almost all three regions with ease. Its grip has slipped mightily since then. If you aligned sales between Switch and PS4 since Switch launched and looked at marketshare it's a vast slide for Sony compared to Wii U and PS4. So it's "peak" as far as year-to-year marketshare is far, far over.
Which means nothing. If the PS4 is selling like crazy Sony doesn't care if they outsell everyone else by a foot or by a mile. Plus, the Switch has had no decernable effect on PS4 sales which likely means that there's very little overlap in their target audience. If they aren't pulling from the same customer pool how is the Switch supposed to make the PS5 come sooner?
Bet with Adamblaziken:
I bet that on launch the Nintendo Switch will have no built in in-game voice chat. He bets that it will. The winner gets six months of avatar control over the other user.