Also there are way more then just 11 vaccines all in all.
It means that the outcome of vaccine studies which complete in 2023, e.g. medium-term adverse effects, identification of specific risk pools, mitigations for adverse effects, will primarily benefit those who receive treatment after the studies complete in 2023.
Any beneficial information from a study completing in 2023 would self-evidently not be available in 2021 and 2022, i.e. science would have yielded new scientific knowledge. Participating in an ongoing scientific procedure with partial data is a risk-benefit decision, but that does not make it any less of an experiment, when there is ongoing, parallel research, clinical trials and scientists working diligently to answer open questions.
The U.S. NIH says otherwise, e.g. here is one of the ongoing clinical studies, which continues through March 2023, https://clinicaltrials.gov/ct2/show/NCT04848584
> covid-19 vaccinesWHO lists 11 vaccines and 4 types, each with different mechanisms of action, effectiveness and safety, https://covid19.trackvaccines.org/agency/who/