Counter-intuitively, it also gives permission for people to speak who otherwise would be too shy.
I'm wondering if that has to do with internal "speed"/timing issues. My ex was a slow talking, quiet sort (and shy/introverted) and I tend to talk a lot and talk fast. A big issue in our marriage was when we argued and I felt like I took really huge pauses to try to get him to speak but he still wouldn't speak so I would resume talking to fill the silence. His take on it was that I never ever shut up and there was no way to get a word in edgewise. I imagine if we had overcome this issue, the marriage would have gone a great deal more smoothly. I had to actively teach our younger son, who is more like his father in this regard, to simply "interrupt" me and his fast-talking older brother. Otherwise, he feels like we don't "let" him talk. There is a big disconnect in the internal timing here -- he seems to not be able to judge how/when to jump in the way his brother and I do. So when he simply "interrupts" us, I defend it if his brother gets irritated or something.
Definitely can relate to this situation (of your ex). It definitely can be a case of difficulty "judg[ing] how/when to jump in", I certainly am below-average on that measure.
However, a separate but related trait is that I often find myself internally running through several iterations of what I want to say, only to realize that by the time I've winnowed it down to the relevant info and am ready to speak, the conversation has moved on.
I'm wondering if that has to do with internal "speed"/timing issues. My ex was a slow talking, quiet sort (and shy/introverted) and I tend to talk a lot and talk fast. A big issue in our marriage was when we argued and I felt like I took really huge pauses to try to get him to speak but he still wouldn't speak so I would resume talking to fill the silence. His take on it was that I never ever shut up and there was no way to get a word in edgewise. I imagine if we had overcome this issue, the marriage would have gone a great deal more smoothly. I had to actively teach our younger son, who is more like his father in this regard, to simply "interrupt" me and his fast-talking older brother. Otherwise, he feels like we don't "let" him talk. There is a big disconnect in the internal timing here -- he seems to not be able to judge how/when to jump in the way his brother and I do. So when he simply "interrupts" us, I defend it if his brother gets irritated or something.