The purpose of vaccines is to simulate the natural process which leads to immunity, while lowering the risk of serious illness. The "gold standard" is natural immunity, not vaccines.
It would be helpful if you could share one or more sources for your claim.
I don’t think that’s how it works. If you have sources showing that natural immunity = sterilizing immunity, please share, otherwise we have to assume the existing consensus that sterilizing immunity is a special condition not usually achieved after infection for airborne viruses.
It would be helpful if you could share one or more sources for your claim.