I agree to some extent that Nintendo is offering an unique selection of games where you can invite friends to personally have fun with you, while on PS4/Xbox this is almost non-existent. I had a lot of fun with Mario Kart 8 (Wii U) and Mario Party (emulator) just yesterday with my friends.
HOWEVER, it's too soon to assume that Switch will bring the audience of the Wii back to consoles. It's not even an year old.
Plus, PlayStation is making new kinds of games for all genres, including titles like PlayLink, where you play with your smartphone, and PS VR. They deliver games of quality that are also innovative and are the main responsibles for the success of the industry, just see the sales. Nintendo had success with Wii and 3DS, and failed everything else.
3DS, Wii, PSP, Vita, PS2, PS3, PS4 & Steam.