More realistically, even if enough of them have antibodies to create herd immunity. (Via making it impractical for the virus to transmit to a vulnerable host)
I think a likely outcome is that the current outbreak dies down, then it either flares up again from some undetected cases or is reintroduced from another country. But then, with the initial media attention elsewhere and COVID-19 symptoms basically looking like the flu, they'll just let the sick die rather than re-introduce draconian quarantine measures.
As an RNA virus, it would be extremely difficult for SARS-COV-2 to establish persistence. I'm not aware of any known mechanism by which that could happen. It's been proposed that some COV's may have neurotropic capability [1] that might allow them to achieve latency, but it's just that -- a proposal.
