One of my pet peeves. And it isn't just younger generations. I grew up in the 60s and early 70s and people my age do it all the time. There are occasions where the only way I can finish anything i to continue talking over the interrupters. Sometimes that tactic shuts them up but other times they plow on ahead.
Or, they probably have adhd from eating gluten! Ha!
But, really...I know what you're talking about. Even commercials on television show children acting like their parents are the idiots by rolling their eyes, the tone of their voice, blahblahblah. I don't know when/where it started. And, why parents let their children do this to them. I'm glad I don't have kids.