as far as i understand it, the "vaccines" you are referring to turn the host into a spike protein factory, using the hosts own cells, via an mRNA payload, carried by a virus or a lipid.

the very same spike proteins are on the surface of the SARS-CoV-2, as they are on all corona virus "variant", making them have a lot to do with each other.

What i have yet to see is any reason why making spike proteins, that cause the disease you're trying to protect against, would protect you from the disease.

the reason i have yet to see any reason, is there is no reason.