I mean, I don't want to sound callous, but 'herd immunity' as a term has been used for ages now - even in non-scientific vocab. It's one of the major logical arguments to make when you're trying to argue with an anti-vaxxer with facts (if for some reason you're doing that), because it's the best way to point out how a chunk of the population depends on everyone else's immune systems and vaccinations to help them, because of their own damaged immune systems. Achieving herd immunity is actually going to be good for the people most susceptible to covid-19, because it means that their chances of contracting the disease have reduced significantly.
Of course, this may have all been a joke that went over my head, but if it isn't, herd immunity's a common and longstanding term that does better than "gentle" language would at making it clear how much everyone who can needs to be vaccinated (in cases of general illnesses) or develop a natural immunity to a disease (in the case of nCoV19) in order to safeguard the most vulnerable - a reminder that we are ultimately a collectivist species and social animals for clear reasons.