People avoiding medical treatment is awkward in the figures, because - medical treatment sometimes kills people. First link I found suggests that medical treatments cause 800,000 deaths per year in the USA.
If medical treatments are really down, I'd guess we might actually expect mortality figures to be temporarily down (but, higher later).
That number pops up all the time in clickbait headlines, but the study behind it doesn't really support the claim.
There is a pretty substantial difference between "Deaths caused by medical mistakes" and "Deaths that occur in a certain timeframe after a medical mistake occurs" (which is what the study actually looked at) are two very different things.
The sicker someone is, the more likely they are to receive healthcare (so there are more opportunities for mistakes). Also, the sicker someone is, the more likely they are to die. Those two combine to result in a lot of folks that die shortly after a medical mistake, even if the mistake was very minor, and didn't contribute in any way to their death.
Whenever you take any surgery (for example), the meaningful risk of immediate death is balanced against the benefit of better quality of life later.
If you measure the impact of medical treatments only on the day they are taken, you'll only find evidence that a bunch of people have died who wouldn't have otherwise died on that day.
You can't then observe the benefit until some time has passed.