While I see why it is very helpful for scientific reasons to know who is more at risk, I don't know if it actually helps "to protect the most vulnerable". Are people who think they are more at risk to stay at home without any physical contact for maybe years? (My grandparents are already doing that, they are staying at home, no person enters their home anymore, although in my opinion they need help, at least with the household and maybe even more...) Do we want to extend that to those who are statistically more at risk?
Because that's the implication in my opinion: Some people (me for instance, I'm female, not 40, not the weight I would wish, but not obese, no COPD, type 0 if I remember correctly) can go out, be happy, not worry, the others can or shall stay at home...
If there is a certain medical measure that can be assumed to be effective in a specific case of factors, than the knowledge helps. Otherwise it might just lead to social divisions and thinking of "who cares, not my problem" vs. "oh my god, I'm highly at risk".