ONCE YOU POP, THE FUN DON'T STOP
The fun usually does stop for me, once I pop.
To answer your question, if people tell you to "Shut up and get better" and they're clearly just abusing the Stage Interactables, like really JUST focusing completely on the Stage Interactables and not even the actual fight between you two, then they lose credibility with that statement.
But, if your opponent is already a good player and picks the stage for an added advantage, then he's playing to win. Which is fine.
My Main is Batman, so I actually don't have problems with interactables of any kind. I can dodge every one of them with ease.
On the subject of Interactables, I do think they add another layer to the gameplay, obviously. Whether they're Scrubby or not, it's dependent on the Stage. e.g. Metro Rooftop, Watchtower (Either level), and Ferris Aircraft. Those get abused.
Banning Interactables talk is always happening. It won't really affect me if that were to happen. But people say that some characters really benefit from it. So, I don't know about straight up banning them.
NRS should just tweak the damage on Interactables. Which has been suggested by many people already.