The thing about these stats is that people seem to be upset that every cause is included in someone's death. That's how it's always been done and part of why heart disease is so high up there in the death rate. It's compounded by
If you want to say that these things exonerate the covid-19 numbers from being so high then it's just not comparing apples to apples at that point. It's not unique to any important health stats that we include people with pre-existing conditions. All of the contributory problems result in the death, so they all officially share the blame. The bottom line is that 43%+ people in the US are vulnerable to covid-19. You saying we're protecting ourselves from 6% of 6% is ignorant of the reason we wear masks, in actuality we're wearing them to protect 100% of the 6%, particularly the 94% that's high risk (~22,000,000).
There are going to be examples of heart disease, but if it's together with symptomatic lung issues then it's dishonest to say covid-19 doesn't play a part. I've known 3 people now who have had it and the 2 symptomatic people have said breathing is a constant struggle. They're all in the 20's and fairly healthy.
If your argument is to let all of the unhealthy people die you run into wealth divides very quickly. Respirators give people a chance to recover, not all hospitals have enough of them and that's primarily in poor areas. The argument quickly becomes "let the poor unhealthy or old people die, everyone else will be fine." I don't think that's very American of us, nor something for anyone to be okay with.