It's not a binary choice between life as normal and total shutdown. The whole discussion is about reducing non-essentials to slow down the spread, so the health system can cope with the demand spread over time.
> 2. You can't maintain quarantine for more than a month or two, after which your epidemic simply re-starts, and you don't get to re-impose the quarantine then because the first quarantine "failed".
Again, not a binary situation. Given the degree of individualism and freedom, that's unlikely to work anyway.
> 3. Vaccine is over a year out in the best case, assuming it works at all.
Agreed
> If it's anything like the flu vaccine, chances of it working reliably on mutated strains are approximately nil.
While this is likely -- I'm not an expert, so I'd rather refrain from such categorical statements.
> 4. Younger people tolerate the disease much better, and if they build up immunity to it while the senior population self-isolates, the overall number of deaths could be minimized.
False dichotomy -- younger people can still be better protected by reducing non-essential contacts.
> 5. Due to how widespread and virulent this is, it will just become the "new flu", and it will come back with mutations every year. We can't do what we're doing now every year, at least not if the goal is to minimize deaths.
That's right, but counting primarily on herd immunity while neglecting other measures does NOT minimize deaths.