I agree that the vaccine is likely low risk, particularly in the short-term, but this technology has been in human bodies for what, about 300 days? No one can definitively say that nothing is coming down the pipes. Again, I think it's probably low risk even in the long term, but I don't know.
According to the
CDC, someone in my age group that contracts COVID has a 0.4% of dying. That includes fat people, diabetics and cancer patients, so it's a fair assumption that my expected survival rate would be a fair amount better than that. Given the unknown regarding the long term affects of mRNA, I'm comfortable with the level of risk that COVID poses to me.