In one study showed that mask laws decreased infections by around 2% after 21 days.
https://www.healthaffairs.org/doi/pdf/10.1377/hlthaff.2020.0...
So there's a good chance that masks don't account for the massive decrease in infections you're seeing in Florida.
I think time will tell if you're correct or OP is correct.
If mask laws are lifted, and infection rate still continues to decrease, that means masks are ineffective and OP is correct.
If mask laws are lifted and infection rates increase again that means you are correct as masks did have an effect.