My, you get so easily into this state that you must really enjoy it. Others are less likely to.
It's good news when people are infected without severe complications. Surely you're aware that the virus is expected to spread to the majority of the population; by declaring it awful that these individuals should have it, do you mean you had others in mind? (Are you really thinking at all?) By what supernatural means are you convinced that herd immunity can't be the solution? Where do you get the idea that "coronavirus antibodies have potentially a very short shelf life"? It seems to be estimated somewhere between 2 years for MERS and 10 for SARS, which would suffice. Most importantly, infection rates aren't the problem; hospitalization is. The two aren't in a fixed ratio, and one without the other is in the long run a good thing. The variability must lie in how some people's immune systems get overwhelmed sending them to the hospital when the vast majority simply cope with mild or no symptoms, which is likely due to the magnitude of the initial viral exposure (or to immunodeficiency) as with many other viruses. Even the much-discussed elderly can have only a mild case.
Predictions about the outcome for any individual, based on what happens on-average for others, wouldn't have foreseen that in the UK we have had a 21 and 37 year-old die from the virus without any underlying medical problem.
I don't believe this virus is going to go away. It seems more likely that it will follow something like the pattern of influenza with outbreaks in the colder months, but that is just my speculation. My point is that 'normal' in the future is unlikely to look like 'normal' in the past and will be 'normal+Covid-19'.
Seen from this perspective, anyone who is infected now and survives is likely to be in a better position to deal with a future infection, so this could indeed be good news for them. But note the words 'likely' and 'could', used here because maybe Coronavirus will mutate in the same way as influenza and present a different challenge each year.
Seen from my perspective being diabetic and having a lung disease, infection poses a very serious threat and wouldn't be good news at all.