There's apparently also a lot of people who straight-up do not know that you can get reinfected. They aren't testing for any illness after they've had their first infection because they think they're already "over with" covid. There is no political interest in informing these people about the decreased immunity given by the newer strains, so I expect this will also depress case numbers until reinfections are common knowledge (e.g. you know multiple people in your social orbit who have gotten covid more than once).