And the only people they can transit it to that would be "at-risk" are people who've had the vaccine available to them for free, for months and chosen explicitly to not get it. That's their choice, and we should not cripple the country over it.
[1] https://www.cdph.ca.gov/Programs/CID/DCDC/Pages/COVID-19/COV...
It's a good thing only about 2.7% of the adult population of US is immunocompromised.
We can't base policy off something that effects an extreme minority of the population, like this 2.7% statistic you cited. We'd never do anything if that were the case...
The affected people should take all necessary precautions available (get vaccinated if applicable, wear a N95 or KN95 mask, shelter isolated at home, etc). Everyone else needs to go back to work, school, stores, restaurants, etc.
Vaccination does not prevent transmission, but it does reduce it.