Russians seem to feel (e.g. the answers and comments to this question or this question or this one) that there is a large difference between sounds produced via palatalization (via interaction with soft vowels or the soft sign ь) and sounds produced via iotation (via interaction with the letter й, the palatal approximant).
However, whenever I try to pronounce the two, I am unable to distinguish them.
Question: Can someone link to an audio recording which makes the distinction between them clear? I.e. how is palatalization supposed to be phonetically different from the effects of the palatal approximant?
How are the sounds produced by the palatal approximant and palatalization different in Slavic languages?
For example, compare лён and почтальон. According to the IPA writing, the former's "o" sound is supposed to be only palatalized but not iotated [lʲɵn], while the latter's (final) "o" sound is both palatalized and iotated [lʲjɵn]. But for the life of me I can't hear the difference.
While a link to an audio recording would be preferred, a detailed description of how the position of one's mouth differs between the two would also be very helpful. That being said, it would probably have to be very detailed, because using the descriptions I have already found, I have not been able to create a perceptible difference.
Note: This might be a duplicate of a previous question, but I don't understand the previous question enough to be sure. In particular, I only know that palatalization = "soft vowels" and palatal approximant = "y-sound in English". The other terms I am trying to pick up as I go, but I have very little experience with all of them and am not confident that I understand any of them correctly.
If nothing else, consider this question to be specific to Slavic languages only (or Russian in particular), and the previous question to be general to all languages.