That's not what that study shows.
The link is for the second sentence. To quote from the abstract:
> Overall, our results indicate that mild infection with SARS-CoV-2 induces robust antigen-specific, long-lived humoral immune memory in humans.
As far as the reports from Israel:
> By contrast, Israelis who were vaccinated were 6.72 times more likely to get infected after the shot than after natural infection, with over 3,000 of the 5,193,499, or 0.0578%, of Israelis who were vaccinated getting infected in the latest wave.
Other research shows that natural immunity is long lasting.
https://www.nature.com/articles/s41586-021-03647-4