I think you've missed the whole point of portability. It's nothing to do with value for money, most people who work won't have time to sit at home and play through Persona 5, Monster Hunter World, Assassin's Creed Origins, and Dragonball FighterZ. They want them on Switch so they can fit them into their schedule while out on the go.
"...as my backlog on PS4 is now too massive for me to keep spending money."
It sounds like you've just written a laborious story about how you bought a bunch of games for less money, that you'll probably never get through anyway, rather than just wait a bit to pay more for a Switch version you can play anywhere and finish any time you like. That's why Japan loves portable systems, they're busy people.
Should've just bought Persona 5 and put the rest of your credit towards pre-orders.
