Serial Offender, fallen off the wagon many times over the decades. I've seen some amazing pushback. A researcher who bellowed "I HAVE NOT FINISHED" so loud, it was like the MTV man-in-a-chair reaction from everyone else. I wasn't the guilty party that time but I could have been. It's often said people believe women do most interrupting when the stats are very good 75% or more in mixed dialogue, is men's speaking time…
I've seen this happen once, to the person in our group of friends who was the most "barker". In that context we all had a laugh about it (when he had in fact finished) and it was a useful correction to the group dynamic.
I've also done the "soft" version of this myself: if someone interrupts you, simply up your volume to the highest projection you can without reaching the level of shouting. The interrupter will realise that you're not giving way and trail off, disoriented, within a few words. It does require being able to signal with your tone that you're not losing your temper, you're simply louder than they are and ignoring the interruption.