Are those people then supposed to take the mRNA vaccines in addition, if not, why are people with natural immunity required to get an additional vaccine (among them J&J)?
[1]https://www.aamc.org/news-insights/so-you-got-jj-vaccine-her...
Can you explain why you don't believe the same would apply to the immune response elicited by vaccines?
There are breakthrough cases in people who are just a couple of months out from their second dose of even Pfizer and Moderna, and not all of these people are in age and risk groups where one would expect a poor immune response. So clearly YMMV with the vaccines as well.
> Another factor I have come across is that it may be that natural immunity is more variant specific while the vaccine results in a immune response to a wider array of variants.
The science actually indicates the opposite of what you suggest. See https://www.nature.com/articles/s41586-021-04060-7
> While individual memory antibodies selected over time by natural infection have greater potency and breadth than antibodies elicited by vaccination, the overall neutralizing potency of plasma is greater following vaccination.
So basically, if you recovered from natural infection, your memory B cells will be "better" than those generated by vaccination in terms of their potency and breadth (which speaks to the potential to deal with variants), but people who have been vaccinated have more potent neutralizing antibodies immediately following vaccination.
The problem, which can be seen in places like Israel, is that the neutralizing antibodies don't stick around forever. In fact, the latest data[1] suggests these antibodies wane quite rapidly (in as little as a couple of months) in those vaccinated with Pfizer. This is discouraging but not surprising. It doesn't make sense for the body to keep high levels of neutralizing antibodies circulating indefinitely every time you're exposed to a new pathogen.
The question: is the world prepared to boost everyone every 2-3 months to keep our veins flowing with high levels of neutralizing antibodies?
[1] https://www.cnn.com/2021/10/06/health/pfizer-vaccine-waning-...
Another factor I have come across is that it may be that natural immunity is more variant specific while the vaccine results in a immune response to a wider array of variants. This seems like it may be valid considering the situation in Brazil[2] and with our understanding of the flu, but I am not sure the mechanism for this.
Lastly (as mentioned in another comment) it can create perverse incentives where people will do something like "covid parties" to gain natural immunity which would make things worse.
The vaccine on the other hand has a dose which is of a known quantity and the response from that dose is well understood across many demographics. So it may come down to the fact that we understand the vaccine response better than natural responses.
I'm not saying whether or not any of this is a good enough reason not to allow for natural immunity to be just as valid, but it's what I have come to understand (which may be incorrect) based on the data we have.
[1] https://wwwnc.cdc.gov/eid/article/27/9/21-1042_article
[2] https://www.bmj.com/content/372/bmj.n394