Especially during the pandemic every argument was had ad nauseam and a (similarity to) certain narrative wasn't perceived as coming from good faith anymore. People were tired of explaining the difference between DNA and RNA, between relative risks of the vaccines and infection, herd immunity, ... . At some point you never knew, if the person you are debating will go full conspiracy nut. Even genuinely skeptical people were often worried because of opportunistic clout chasers were spreading misinformation.
See the comment above where the AstraZeneca vaccine got conflated with mRNA vaccines. Bad start...
There were no vaccination mandates. However, "anti-vaxxers" were offended people decided to keep them out of their groups, shops, communities, ... by vaccination status. They want to have the cake and eat it too. Their idea of discrimination is overreaching and entitled.
"Get the vaccine or lose your job" absolutely is a mandate. This really was a thing.
Well, yes, that's what I was getting at: Freedom cuts both ways here. If you choose to not get vaccinated, others should be allowed to, at the very least, choose not to have you around. Immunity is not a private belief, but has severe, sometimes existential implications for other people.
I assume, it's pretty much the same with guns in the US. You are allowed to own them, carry them, but not allowed to bring them everywhere, if someone's ruling within private jurisdiction forbids it.
Only because it was struck down by courts. The US government did attempt it, and even told employers to abide by it while they appealed (before it was struck down again).