This isn't good sportsmanship to say mid-game and this could easily be considered "verbal abuse" and that is against chess.com's tos. If they report you (likely), then probably some action will happen even if this action is just a warning, or a temporary mute.
Banned is possible of course, but usually this is reserved for more severe cases, or repeated offenses.
On a related note, chess.com is currently working on more lenient guidelines for what is considered "abuse" in the game chat for games with chess.com "friends" of yours. The idea is that friends should be able to playfully trash-talk with each other if they are okay with it.
However, this idea is simply in the works and is NOT part of chess.com yet, so comments like yours (friend or not) are currently not allowed.
So I was in a bullet game with this guy. A good player, and he fought fair. I had just clawed my way back from a losing position after he blundered a bishop. I was still going to be in the fight for my life as I had only 15 seconds left while he had 30. but then, as I captured the piece, he just resigns.
sure the valuation bar was 3 points my way, but I was only up a pawn or two at most, and it was really just that hidden voodoo positional stuff.
I felt that he could have, possibly should have, won the game if he continued, and I was quite disappointed by the fact that he gave up so easily. I wanted to tell him to not resign in positions like that, and i gave him some extra motivation by sending him this message:
"bro we were almost even on material and you had twice the time dont u EVER resign in a position like that ever again or i will take a jackhammer to your balls" --Martin Luther King.
to his credit, before I was blocked, he sent a "thank you, happy thanksgiving"
so the real question is this. will my jackhammer continue to pound? or will danny himself come forth to stop me?