So, I'm genuinely not being disingenuous, but...
If the vaccine does not, or may not prevent transmission, what on earth is the point of a vaccine passport?
If visitors come to a country where Mich of the population is unvaccinated, they could still spread the virus to the unvaccinated, which would potentially become unwell.
If visitors who are unvaccinated come to a country where most have received the vaccination, it really wouldn't matter if they brought the virus in... because the vaccinated population would be protected against it anyway.
If a vaccinated person travels from a country where some are vaccinated and some aren't, they could potentially still contract the virus while abroad, host the virus assymptomatically, and bring it back to their home country, where they could infect vaccinated people.
It just seems like the biggest and most pointless waste of money to me. Or am I missing something?