You still think the Switch will get friend messaging? You poor soul, guess at this point you'll still believe even after the next console is out. :L
More on topic, of course it can improve, but the question is will it. Nintendo had a lot of time to make the service good from the get go, yet they deliberately didn't, infact they even made it worse by cancelling SNES games. Needless to say I doubt it'll get much better.