I do understand this sound on a cognitive-analytic level (some phonetics courses at university help when learning sounds). I can pronounce it, at least passably.
There are big regional variations to pronouncing sj and so on. Fine, I can live with that, just pick one and use it consistently, preferably that of your teacher.
But when it comes to the sound the article is about, I hear something else.
At some point I cut together many instances of words with that sound from Swedish pop songs and told my teacher which sound (IPA) I clearly hear in all those instances. She told me flatly that I'm wrong. Those singers clearly sing another IPA sound.
It must be similar to when Russians try to show me the difference between hard and soft consonants. They tell me they really over-pronunciate now and they sound starkly different, I'm not even sure I hear a difference.