As Quarantines go , 21 days is not really severe.
Couldn't we make the wait comfortable?
I don't think it would be difficult to build a sanitarium out in the country where the persons being quarantined could be made comfortable .
After all most of them won't be sick, provide a golf course , horses to ride , Jacuzzis, perhaps college credit courses... whatever.
Make it four star! Pay them tax free cash!
This might be expensive , but it would be hard to estimate how much more expensive fighting an outbreak in a large city would be.