ujm,
see July article Ali Hamady, JinJu Lee, and Zuzanna A. Loboda “Waning antibody responses in COVID-19: what can we learn from the analysis of other coronaviruses” for a lot of details on antibody and T-cells.
They are saying that antibody response from disease is lower than vaccine, especially for new variants, as vaccines are designed to target multiple parts of the virus.
I would add my own understanding that disease protection varies depending on severity. Having a mild or asymptomatic case may or may not give antibodies (to be confirmed with the test) but may not guarantee longer T-cell response, so you may want to continue measuring antibody levels/
Disease + one vaccine are getting great results, with disease substituting for the first vaccine. This sounds like a reasonable middle way.