There is a lot to agree with here. I’ve been guilty of creating podcast with all your worst nightmares, skype, rambling and more.
But I love podcasts. Two main reasons, one the sound of voices is different, for me, than reading a post; two, I can listen to podcasts while driving to work. I don’t want succinct  information, I want to be able to do the equivalent of rambling for listening, picking up bits and pieces, thinking of something else, paying attention to the traffic.
I remember when I started podcasting there was a txt file going round that explained, by example, how much better plain text was. That is fine if you can look at it, not so much if you are washing the dishes:-)
Enjoyed the rant!