I'm one of those who is always cold. As such I always have a light weight hoodie with me, even as an Arizonan traveling in summer.
But no, I can not simply add that extra layer of clothing to 'solve my problem'. The air I breathe in is still cold and if the flight is 2+ hours (and is freezing) then I will have a sore throat by the time we land.
I accept that I'm "odd". The only solution is to cups my hands over my mouth and nose and 're-breathe- my own air.

But what I actually can not tolerate is having the frigid air blowing on me. It seems that the past couple of years the fans are always run at full blast. My and my seatmates air vents can be full closed and I still have frigid air blowing down my neck. I wonder if this is a "covid thing" having fans on full blast keeps a "top-to-bottom" cabin airflow going. I feel silly wearing my hoodie with the hood on and alternating between sitting on my hands and cupping them over my face.

It's funny how the OP and I have opposite experiences. I generally find AA temps to be better (not as cold) and Delta flights consistently miserably frigid (tho I otherwise prefer DL). The past 2 months (so a sample size of only 8 flights) I've found the AA cabins cold and fans at full blast ... to the point that I've wondered if AA has had a policy to match DL's.