I was watching some performance videos on YouTube and one had an actor sweating excessively. I always notice sweating because I have a physical condition called hyperhidrosis. I sweat for no reason from my forehead. Yes, I've tried everything! :) The best cure has been to just live with it, accept that it's who I am.
Anyway, I have great empathy for all actors. Whether I like or dislike a performance or production, I am always rooting for the actors because I admire anyone brave enough to perform in front of an audience. But I especially appreciate actors who sweat. I notice when the action is off them and they pull a handkerchief out and subtly dab their foreheads. I'm not saying they have the same condition as me. Likely it's a combination of hot lights, makeup, heavy costumes, and nerves regardless of how confident an actor is.
I don't know the point of this thread really. It may just be for actors who read this forum and who are anxious about their uncontrollable sweating, to know there is at least one patron in the audience -- me -- who empathizes and admires your courage.