@Peter3096 @Anonymous
It is controversial if a badge (to opt in or out) would be something discriminatory. It would be a personal decision/choice in front of the pandemic.
However, I think it is plausible that, in the future it may become a "policy" of Airbnb to ask for vaccine certificate from the guests.
If the guest has some medical issue with the vaccine it could have a certificate that says that one can not take the vaccine.
If some air companies ask vaccine certificate and also some countries ask for it as well to enter the country, why it would be so unreasonable if Airbnb asked a certificate as well?
In some cities vaccine certificate is required to go to cinema and theatre.
Of course that it would not be possible to implement some policy now because lots of people has not taken the first of second dose. Anyway, later on it is a matter to be considered.
To demand vaccine certificate is not something new.
Some time ago, long before the pandemic, I visited Bolivia and Peru. It was necessary to be vaccined against a kind of ilness/fever to prevent problens when visiting arqueological sites near the jungles. In other words, a vaccine certificate it was necessary to enter those countries. It is not a discriminatory measure, it is a safe measure.
If one can not be vaccinated, it is better to stay at home instead of getting an ilness in another country.
The same thoguht may aplly to the vaccine against Corona Virus. If someone do not want to get vaccinated, better staying at home instead of spreading the virus or getting sick in another city or country.