The risk is likely somewhere around 1 in 100,000. No medicine has had testing in trials that would reveal that rare of a risk. All new medicines have a chance of this kind of side effect showing up when it enters the market. Unless you are in your 20s and in an extremely low risk area for Covid, or are totally isolating with your entire household, you are almost certainly better off getting whatever vaccine is available to you.
People deserve information to make informed decisions, so I support a short pause in the US for that and the other reasons I mentioned. But if someone declined vaccination at all, or puts off vaccination for months until there’s a longer track record for the vaccines, they are making the wrong bet.
Even the risk band charts that have been posted are about risk of Covid per 12 weeks. The shot is a one-time risk for long-term protection against Covid and all of its consequences (not just death). (All DVST incidents so far have been from the first shot.).
This is complicated, and worth discussing with one’s doctor if there are concerns, but one liners like, “I don’t want to be a beta tester” do not capture a valid reason to delay vaccination.