Technically as long as everyone else you expose to it has a similarly low risk profile and low likelihood of transitively passing it to anyone with a high risk profile, I think it would still be beneficial until herd immunity has already been reached. In practice, of course, that’s incredibly hard to assess except for one’s household members, and household exposure is probably high-dose. So I think I agree with your conclusion, but for slightly different reasons. (Maybe if everyone in your household licks the packages, it would still work? :P)
Technically as long as everyone else you expose to it has a similarly low risk profile and low likelihood of transitively passing it to anyone with a high risk profile, I think it would still be beneficial until herd immunity has already been reached. In practice, of course, that’s incredibly hard to assess except for one’s household members, and household exposure is probably high-dose. So I think I agree with your conclusion, but for slightly different reasons. (Maybe if everyone in your household licks the packages, it would still work? :P)