Miiverse is shit but it could be great. It's a great idea but the execution is horrendous. That doesn't mean they should just scrap it though. They should improve it. They should make it better.
Nintendo seems to just give up on the things once they don't go quite right. At least, that's what they do half of the time. The other half of the time, they're stuck in a rut, trying to do the same crap over and over again until they succeed (or, more likely, fail).
As for Streetpass, it's sort of the same. Some games and apps use it well; some don't. Eventually, if they keep such a feature available for long enough, it will become a natural part of their ecosystem that developers will want to use. Throwing it out, saying the Switch doesn't need it, and then trying to deny that Switch is even a handheld... This seems like another half-assed idea from Nintendo. Would it really have been that much effort to add Miiverse and Streetpass to the Switch? I think it'd have been worth it in the long run.