So much fallacy on this thread lol
The reason is simple OP: Nintendo just don't see them as worth it. We are talking about a device that don't even let you customize its interface, menus and store (and at least the store definitely needs some polish)
Nintendo look to all those apps, saw how small is Switch storage and battery and asked: Why bother using time and resources to run apps that you can use everywhere else?
But I personally sorta disagree with this approach. I would rather use Netflix on my Switch (that I can use as a Tablet) than on my smartphone, plus the convenience of having all in a single device is just too practical to not enjoy it. More options are never a bad thing and I can't understand customers not liking it