Called the Southwest Chase number on my card. Told them I'd just been charged $100 fee and asked if they could offer any credit for this year. They asked if I was considering canceling, and of course I said yes (which I'd forgotten to mention / lead with.)
I was immediately offered a $100 statement credit and took it. Whole call took less than a minute. I believe I got a spend-based offer last year, and I think I also got some offer or credit the year prior.