Here are the two recent studies I've seen that suggest reinfections are not rare and have similar severity to the first. Qatar's reports have been good so I wouldn't discount their results, and it's possible that the 81 study meta-review and the VA system data don't accurately capture what's really happening, but still they are the strongest cases I've seen in the area.
I haven't seen any case that protection from infection is better than at least the mRNA vaccines, only that it's inconsistent and wanes relatively rapidly. Where'd you find that?
Burden of PCR-Confirmed SARS-CoV-2 Reinfection in the U.S. Veterans Administration, March 2020 – January 2022
https://www.medrxiv.org/content/10.1101/2022.03.20.22272571v...
The mystery of COVID-19 reinfections: A global systematic review and meta-analysis
https://pubmed.ncbi.nlm.nih.gov/34900250/