I disagree completely. Millennials on average make an effort to embrace gen-z slang. And millenials actually respect the fact that new gens have new lingo. And they're open to change. Boomers just fucking hate all newer gen lingo and think that their language is superior because boomers only care about themselves. I think millenials will continue to be flexible when it comes to adopting newer slang. Sure. Younger gens will always make fun of the olds, and that's to be expected, and it's understandable, but it won't be nearly as bad as millenials making fun of their boomer parents for being completely tone deaf.
And then there's us Gen-X folk standing off to the side watching other generations bitch at each other because they always forget about us. Maybe we just need to be called "The Forgotten Generation".