Listening to Ira Glass the other day, I noticed his 'l', to my ears, sounds exclusively velar with little to no dental component. Here's a clip (he says the word "like" a couple times in rapid succession):
Is this an American regional variant? I hear it more on his pronunciation of light 'l' and though I also hear more nasality in his voice. The American Journalism Review in this article called his voice "adenoidal" and said it has a "slight stutter, not a speech defect, but a verbal tic, a device" but I am not hearing a stutter, nor a tic. I can't tell if this article acknowledges what I'm hearing or is commenting more on the cadence and style of his speech, rather than focusing on the way he pronounces the letter 'l'.
I realize it could be caused by an anatomical or physiological difference, but I couldn't find a technical description that mentioned specifically pronouncing 'l' in this way as an articulation disorder (unlike the heaps of descriptions of the more common "ar" -> "aw" rhoticism problems).
Another American English speaker I've noticed with this speech difference (who also has a public presence) is Ben Shapiro, though to a lesser degree. Here's a clip (I hear it in "tolerance", but less so in the words "mayflower" and "religious"):