> If instead, we start acquiring immunity in low-risk populations, at a rate that the hospitals can sustain, we'll have a degree of herd immunity and a portion of the population that can no longer spread it.

A fair portion of low-risk people will require intervention. Given that a lot more people are low than high risk, you're still overwhelming the health system, and all those low-risk people are still going to interact with others while they are asymptomatic but transmissible.