Interesting point I heard about why we don’t (yet) have a vaccine for HIV where we do for COVID - the human body can fight COVID. Ie we mount an immune response and some people survive and recover on their own. This is largely not true with HIV - the human body hasalmost no ability to mount its own response.

Making a vaccine is more straightforward (ie we expect to be able to) when we know there is a response by our own immune systems - hence we expected to be able to make a COVID vaccine (although the time scale is still an amazing accomplishment - thanks 20+ years of mRNA research!). And we are still working on a vaccine for HIV.

I know, but with the technology we are able to employ nowadays I think it's reasonable to push for vaccines that protect people for 20 years like the one for hepatitis. Hell, now we can even think about curing cancer with mRNA, I think a strong flu/corona virus might be within our limits