Why are you assuming that only school districts will be interested in keeping people safe? Have you seen data to that effect?

Anecdotally I can think of at least one person whose employer required him to get vaccinated in order to start traveling for his sales related job again. As a manager he didn't think he could do his job effectively from home forever so he begrudgingly got vaccinated. Other than him, and I don't actually know him, he's a friend of a friend, I don't know of anyone else being "forced" to get vaccinated but that may be because most of my friends have been vaccinated without anyone requiring them to.