Some people refuse to believe the truth when it's simple, because they think EVERYTHING must be complex. There's also the back-slapping "I'm so clever I know what many people don't" angle to boost their enthusiasm for them...
Roger that.
B.t.w. i said it still might have been a russian sub.
But is also has become an annoying stereotype to make Russia responsible for all hidden operations, regardless by what country.
Then, do not believe
everything the media tell you.
Facts:
Mr. Palme was killed, apparently because of some political aspects.
There was one russian sub (speaking of evidence) beached, back then in the 80ies.
Sub intrusions into swedish waters have a long record, and most have been proved to be US and 'NATO' subs.
Some have been sea lions, no joke (but maybe russian ones, ok)
NATO does not like politicians of befriended countries, being friends with the russians.
If you rule out the most unlikely scenario, connect some dots and then think of who gets the most out of a situation, you are usually not far from what really happened.
Ok lets end this here.