The thing is, even if people who only have natural immunity have more protection than people who only got vaccinated, getting vaccinated after recovering from Covid still increases your level of immunity.
This does lead to some funny incentives. The only restrictions are on the symptomatic, so if I’m vaccinated and have access to a supply of SARS-CoV-2, it’s in my best interest to be regularly dosing myself with SARS-CoV-2 in order to avoid my immunity dropping enough to ever develop symptoms.