The logical issue your friend is ignoring is that the disease (covid) is proven to be highly dangerous. The vaccine might be slightly dangerous (depending on who you believe). But clearly there are no remotely credible claims of hordes of people dropping dead of mRNA vaccines like there are for covid. So just from a lesser risk stand point, your friend should get the vaccine.
Good point about new risky thing lol! And I so firmly don’t want covid that, to my knowledge I haven’t had it. And I rather desperately don’t want long covid. THAT concern drives me more than simple covid. I’m cautious enough that people make fun of me, but too bad.