Let it go. Other than you being frustrated by what you consider to be a rude person, who was probably just following rules, you got your way. Even if you were forced to gate check, what is the big deal?? A loss of 5-10 mins while waiting on the jetway?

I fly tomorrow on a CRJ- I know my rollaboard will fit, as its a flight I take often. I pulled attitude once when told I had to check. I lost, and had it checked. The result is I felt like a pr!ck for making such a deal out of nothing, to a FA that turned out to be really nice. Now I just tag it.

IMHO, this lands squarely under the umbrella of “pick your battles.”