Considering the new metrics adopted by the CDC, it would likely take a surge in hospitalizations among fully vaccinated and/or previously infected. And even then, you're talking maybe indoor masking again. That's it.
AstraZeneca did have lower vaccine efficacy in the first trials, but Europe has much, much higher booster rates than the U.S., and a lot of those boosters were Pfizer or Moderna doses given to people who previously received AZ.
The mask rule didn't cause that, the delta surge did. Universal and SeaWorld also reported dips in attendance around August when Florida was getting slammed by delta. And Disney said the slowdown only lasted a few weeks, but the mask rule stayed, so you've got no basis to believe that masks were what made people stay away.
35 people? The doctor you quoted has 623,000 Twitter followers.