Sorry to hear all that. Hope you recover quickly.
I think people seriously underestimate the potency of COVID in general, because of how light their initial infections were.
However, following the mass immunisation, our immunity is waining. Additionally, new variants appear. These new variants are not less severe in strength, as media tell us. They still kill, especially those that are unvaccinated. It's only because of being vaccinated, the *symptoms* of an infection are less noticeable and less severe.
I firmly believe that mask wearing should be reintroduced, especially in winter months and crowded spaces like public transport or in school, and I'm very concerned to see that gradually, we revert to our old habits. For example, in my local church, the priest hasn't been disinfecting his hands before distribution of communion for months now. I'm one of the very very few that disinfects their keyboard in the office.
All that really concerns me. But also how little basic information people have about how vaccines work and how viruses mutate.