Regarding masks: Wearing a covering is better than not wearing a covering. In the aggregate, people wearing coverings will reduce the spread. There is practically no cost/risk to wearing one (relative to the risks associated with covid).
Regarding vaccines: To the best of my understanding, having the vaccine makes you more likely to have sufficient antibodies than someone who doesn't have the vaccine, regardless of whether or not said person had covid. In the aggregate, vaccinating will reduce the spread. There is practically no cost/risk to getting vaccinated (relative to the risks associated with covid).
Stop making strawmen out of your favorite cherrypicked facts.
As to your proposed solution of requiring antibody tests or PCR tests: That sounds good. The fact that I haven't heard any institutions, governments, or businesses going that direction, however, leads me to believe it's either not practical to implement, or it's not as effective as you and I think it should be, for whatever reason.