While I agree with you that people should get vaccinated (if they want. Their body their choice), I feel like the argument of "to what extent other people's selfish choices should be allowed to endanger my life and livelihood" doesn't hold up.

You probably live in some developed country. If it's the US or Canada, I can say for sure that you live in a country that was founded on the exploitation of others. We continue to knowingly benefit off of such exploitation by importing and purchasing products produced by cheap and often abusive labour. We use electronic devices whose manufacture is mostly in China and other such countries where there is recorded abuses and in some cases downright modern day slavery. We continue to use these devices despite knowing that many of their essential metals are mined by exploited children in Africa.

I'm trying to understand exactly to what extent our selfish choices should be allowed to endanger others' lives and livelihoods

Then things might be different, but in our present reality it was always transparently clear to anyone who had eyes to see that the justification for coercination was founded on nothing more than hysteria, lies and wishful thinking.

This take has a straw man vibe. Who cares about the "what if"? Let's address what happened yesterday and how that impacts today.

It matters because vaccination has slowed both the severity and rate of spread of the disease, due to a reduced viral load shedded by the vaccinated individual.

It isn't a binary yes or no, but it has been a gradient. And every policy decision is made on a gradient of harm/benefit. So yes, it is entirely relevant about what the ethics of the hypothetical would be.

Not getting vaccinated is an action that directly harms other people, for what turns out to be no net gain. Requiring vaccination... Is an action that directly harms a few holdouts for some net gain for the rest. None of this is an absolute ethical question, and the degrees of harm and gain are this completely relevant to it.