I’m not sure your explanation is sound. Studies have shown doctors/nurses get sick (pre-Covid) at more or less the same rate as the rest of the population, despite increased exposure to circulating colds and flus. Explanations ranged from “they get vaccinated more” to “background exposure to very low payloads primes the immune system and keeps them healthier.”

I am thinking that maybe doctors/nurses have two factors that cancel out so it makes their infected numbers look like the rest of the population:

- higher exposure

but also

- better, and stricter safety measures that are really followed

I hate to put it in these terms, but do you have credible peer reviewed literature on this claim? What you're saying is exactly what state media & state authorities started espousing after everyone realized the vaccine didn't offer the protection everyone had assumed and been promised. I'm wondering if there is any actual evidence for their claims or if it's just saving face and moving goal posts.