I left Sweden 5 years ago and I more or less agree with the post. It seems to have some undertones i don't entirely appreciate but on the whole it should serve as a necessary reality check if taken with a pinch of salt. It brings up many points that are worth discussing at length but which are essentially verboten in Swedish society. Even if it does overstate or sensationalize somewhat.
I doubt he is leaving specifically because it has abandoned some socialist ideals. For me it has more to do with not wanting to be part of the mass delusion, not wanting to constantly fit your opinions to an ever narrowing hallway of acceptable ideas and speech (not because they couldn't but because they shouldn't have to). At least when you don't live there you don't have to see and live it day in and day out. If anything I have grown more fond of Sweden and the ideals it represents since moving, because I am not forced to come to terms with its realities on a daily basis.