I second this. I had debilitating underarm sweat and continually ruined shirts with pit stains. I switched from antiperspirant to a simple deodorant. I sweat SO much less in the arm pit area and I never sweat through my shirts anymore (unless I'm working out, of course).

Undershirts have been a good win as well - keeps the chemicals off my real shirt, and if you get high-end ones, they're light and breathable and don't make me any warmer.

I can't believe antiperspirant continues to exist as a product. Must be working for somebody.