It makes you wonder about the author's death. Even though it was fiction, I imagine there were people not happy about the trilogy.
The real Steig Larsson actually edited a radical investigative magazine or periodical not entirely unlike the one that his fictional alter-ego does in the books and - in real life - received death threats from the ultra-right. And his partner in real life seems to have played a role not entirely dissimilar to that of Eva in the books. Likewise, I get the sense that some other aspects of his books have a sort of quasi-autobiographical feel to them. Clearly, it's a classical thriller writing device, to use the "skeleton" - or excuse - of an investigation or murder to allow you to focus a sort of forensic (interrogating) microscope on your own society.
The fact that Sweden (along with the rest of Scandinavia) regularly tops the UNDP HDI (Human Development Index), and TI (Transparency International) etc ratings, and enjoys a sterling reputation for public probity, excellent public services, accountable and transparent Government, honest police forces, a commendable amount of money spent in foreign aid - and top class colleagues when working abroad on international missions (as I can attest), excellent gender rights and laws and protections, green legislation, etc, etc all means that when someone writes racy thrillers about the seedy sleazy and very imperfect underbelly of such a notionally perfect society, it causes waves.
I've no doubt that Larsson's death was not greeted with grief by those who disliked him. However, his lifestyle, (and it's written about non-stop in the books), endless coffees, too much smoking, drinking, no exercise, endless stress, not eating properly while addicted to the adrenaline rush of approaching deadlines.....well, I suspect this also may have contributed to his death at the age of 50 from a heart attack having run (run!) up several flights of stairs because the elevator was broken.