Yes, it is very realistic to lock poor people in the slums in their metal barracks to let them be cooked to death, before they starve to death, because they lost every income being locked in and their government is not competent or rich enough, to provide with basic supply.
But yes, Covid19 could be erridicated this way.
Seriously,
"More than 820 million people are hungry globally"
"https://www.who.int/news-room/detail/15-07-2019-world-hunger...
820 million people on this earth were hungry in 2019.
When you are hungry, really hungry, which is not something most people in the western world know about, and also have only limited dirty water supply, then you have other problems, than a new disease, all the rich, old people are scared about.
So no, it is not at all realistic, to have the world in its current state, in effective lock-down, without causing more harm, than good. Unless you don't care about the poor in the first place.