That was never Sweden's strategy though. I don't know how or where this idea started, but it's bogus. Ultimately you have to blame the "simplified soundbite" news reporting (and politicians!) of today (just the word "herd immunity" eliminates the need for a lot of complicated explanation), but where exactly the original erroneous connection appeared I've never seen determined. It just sounded great to the libertards and conservafrauds so they grabbed it and ran with it, and they would have grabbed it and run with it even if they knew it was a bogus theory because they're Just That Shitty as a group of people.Seems clear the 'herd immunity through infection' idea (which I've seen being relentlessly pushed by libertarians across the web since the pandemic began - usually with the standard 'I'm so much smarter than everyone else' attitude that libertarians tend to have) really didn't pan out.
The actual strategy was to keep the number of daily new infections below hospitals' ability to cope with them by attempting to limit the spread of the disease through enforced social distancing and (interestingly) NOT shutting down schools for pre-high school aged children.
The latter because A: if you shut down schools the kids are going to require babysitting, and that would either put many kids with their grandparents who are the most vulnerable group in society (not good!) or else keep parents away from work - potentially in hospitals or other occupations critical to society. And B: young kids don't contract covid very easily, and they're going to naturally congregate to play with each other anyway so might as well keep 'em in school.