As an atheist I do not believe that the individual life of a person has an absolute and intrinsic value. Hence my question: What is the objection against temporarily practicing euthanasia in an exceptional situation like now ("Corona" ).

For example, one could stipulate that the following persons would no longer receive intensive medical care, but in the case of a serious Covid19 infection would only be sedated, so that they could die peacefully and without suffering:
over 60 and two pre-existing conditions (for example diabetes and hypertension); over 70 and one pre-existing condition; and everybody over 80.

In this case, the intensive care units would not be overburdened, the health care system would not reach its limit and a shutdown for the whole society - with all the negative side effects - could generally be avoided. (By the way: In Sweden, something similar has actually been practiced, that is why they had more deaths due to Covid that Norway, Finland and Denmark combined).

I know that such a thing is impossible in my country (Germany) for historical reasons, but what are the general (philosophical) arguments against it?