Maybe we should operate more like c/vegan where everything from omnivore apologia to overt antiveganism (analogous to the above anti-precaution/anti-max/anti-vax-apologia) is forbidden, and posting/commenting as much gets you a ban?
The !vegan@hexbear.net sidebar has lots of resources that lurkers can use to educate themselves before posting, but the !covid@hexbear.net sidebar does not. If the sidebar includes resources about dentist safety, moderating comments that express unfamiliarity with or opposition to those resources seems reasonable.