Absolutely it should be people’s own choice, and it is people’s own choice, but part of making that choice is acknowledging you are making it!
So if you choose not to have it, okay that’s your choice. You can’t control whether people at your work or people on Mumsnet think it was the wrong choice, but that doesn’t stop it being your choice. You can’t say “it only counts as my choice if nobody ever expressed any views about whether it’s a good thing or not.” They get to have those views, and you get to make your choice.
If you choose to have it, then okay, that’s your choice. So you are making it. You are not being frogmarched to the vaccine centre, you are choosing to go. You can’t say “yes I will get the vaccine, but also I would like you to put on record that I don’t agree to this and you’re making me. What, leave? Oh no I’m not going to leave, I’m still going to get the vaccine. But you’re making me.”
It is your choice. Not everyone’s going to agree with what you choose, but so what? It’s your body, it’s your choice, just make it and own it and move on.