Here is the million-dollar question. If the shot does not prevent you from getting covid, and you can still be contagious. Why do they need a national database of people and immunity cards? What's the purpose of having a database of people who will supposedly only get less sick but can still transmit and carry the virus?
The only reason I can think of is to collect data to monitor long term impact across various demographics. Keep in mind that before this month there has never been a mRNA "vaccine" approved for human use and previous mRNA studies against rabies, Zika and HIV only achieved lackluster testing results in animal studies.