According to my good old Russian learning textbooks, the sound ж in Russian is retroflex (/ʐ/), that is to say it should be pronounced with the tip of the tongue pushed against the palate. Now, in my experience, I’ve noticed that most Russian speakers actually don’t pronounce it this way. For example, Putin pronounces an unequivocal voiced postalveolar fricative (/ʒ/, as in "casual" in English, or "jardin" in French).
But you do occasionally hear this retroflex ж pop up in the speech of some Russians. See, for instance, this forvo page https://forvo.com/word/%D0%B6%D0%B5%D1%81%D1%82%D1%8C/ where the first pronunciation (RomeoWhite) is retroflex while the last one (Opndoor) is a voiced postalveolar fricative (as in "casual").
Another example there https://forvo.com/word/%D0%B6%D0%B0%D1%80%D0%BA%D0%BE/#ru where you can hear /ʒ/ in the first example (multimaxfm), but a distinct /ʐ/ in the third rendering (Cheeka).
My question is, Is this the old, traditional way of pronouncing the phoneme ж (Soviet or even pre-Soviet era)? Or is this more to do with geography, with some regions privileging one pronunciation over the other?
Despite my asking several Russian acquaintances, none of them has been able to provide a clear answer as they couldn’t hear the difference or didn’t care.
as they couldn’t hear the difference or didn’t care— no-one actually cares about phonology of their native language, they just speak it.