Hobbes, not sure what your question is. I think the "what if" part is unlikely -- that no vaccine can be made available.
I suppose in that situation, that most of us would then likely contract the virus, and most would survive, and the surviving herd would then continue on. On the other hand, if those who have contracted it can get a recurrence of the sickness, we could be in for a difficult future.
I'm pretty hopeful that a vaccine will be available, and also that once contracted (or vaccinated), that we can be free of COVID-19 for a decent period of time ( a year or two? ). It would be great if we could be free forever, but that's probably too much to hope for.
