Please enlighten me as to what their real objective is. It's obviously not killing as few people as possible.
Their objective appears to be killing as few people as possible... in the long run.
Do they have a higher infection rate currently than the would have if they'd locked their country down? Of course. That's the idea: they want the virus to spread through their populace in such a way as to protect them in the long term against possible "second waves," and etc. The higher infection rate right now isn't a bug in the system, it's the design.
It's also not inconsistent with what we were all talking about just a couple of months ago: "flattening the curve." Sweden's approach initially raised alarms because people believed that their health resources would be quickly overwhelmed, running out of ventilators, hospital beds, and so forth. Well, have they? (Does anyone else remember the actual conversations and why we locked down, in the first place?) It seems to me that they've managed the spread so as to "flatten the curve," but did not clamp down so tightly as other places. So the virus spreads somewhat more there, albeit not catastrophically so, which again, is precisely what they intend.
Will that approach work out for Sweden over time? I have no idea. I don't know whether "herd immunity" is possible, or whether people will be reinfected, or whether the disease will come back in the fall, or what it will look like for countries that have maintained lockdowns that then open things back up (especially given populations that may not endure these measures indefinitely, and push back against them), or when an effective vaccine will be available -- if it ever will. If Donald Trump is right and Covid simply disappears in the summer, "like a miracle," then Sweden surely made a bad decision. But I don't tend to bet on Trump.