I don't understand. 8 out of 25 million is not good enough for you?
Pollution probably (because its not proven) kills more than 8 in 25 million people each year yet we have not done anything like this for that.
It is currently undisputed that having been infected with Covid makes your body create antibodies, and that those antibodies will help keep you immune from subsequent infection for some time. It is mostly agreed upon that the shortest amount of time that immunity lasts is between 3-6 months. Most also agree that the immunity will probably last longer, but no one knows yet how long. Given that the vast majority if those 25 million infections occured within the accepted minimum immunity period of 3-6 months, those cases do nothing but confirm that initial time frame. Beyond 6 months, the science is very much undetermined.
With regards to the frum community in particular, the bulk of our infections occured around 6 months ago. Other places or communities that had large outbreaks of the virus around that time have managed to keep the virus out of their areas. We can't look to them for data on reinfection because they haven't been exposed a second time yet. Unfortunately, as
@S209 pointed out earlier, the frum community may very well be the guinea pigs when it comes to collecting reinfection data. Now that doesn't mean reinfections will be rampant. It could turn out that antibodies last for 2 years in most people. But it does mean that the book is still being written on the subject, and to assume immunity when we know nothing solid about it would be foolish.