There's more variables here than the doctor is looking at. If you just used raw statistics then the US should be tapering off in deaths and about done like Sweden supposedly is. We would have roughly 180-200k total deaths from COVID if you use the swedish per capita deaths rate. We'll probably beat that easily.
We need to remember no country is created equal. Some have better healthcare system than others, and everyone has different customs. Sweden is know for already being a socially distant country. My old roommate lived there for a year and kind of hated how nobody socialized and went out after work. If people aren't interacting a lot that's another way to slow/stop a virus. I'd think you would reach an immunity much faster that way because some of the population has already been infected, but you've also naturally reduced the likelihood of transmission with less interactions.