If geography (and point of first case) didn’t matter then a comp of Italy or the U.K. might matter, but in Scandinavia where first cases all happened about the same time, all the countries have similar social norms, and similar climate, Sweden has a much higher fatality rate per capita.
As per your Stanford study, a recent study published in the Journal of the Royal Society of Medicine Refuted that hypothesis and states the Sweden is nowhere near herd immunity. https://www.rsm.ac.uk/media-releases/20 ... terialise/