> If by some very low chance this introduces an inheritable change, and if by an even lower chance that inheritable change leads to genetic collapse in 10-20 ge

> If by some very low chance this introduces an inheritable change, and if by an even lower chance that inheritable change leads to genetic collapse in 10-20 generations - just to be very clear, this is extremely unlikely - we have opened the window to humanity's end. That's such a vague, unqualified (in the "lacking specificity" sense) concern, that you could apply that to practically any new technology or medical treatment. 10-20 generations is 250-500 years, if somehow this particular vaccine did cause inheritable damage, I'm sure that medical technology would be advanced enough at that point to find a solution. And on that timescale there's also much more tangible and evidential existential crises, like climate change and nuclear war.