me_irl

You're just getting old. Things have perhaps gotten a little faster in general, but Gen Z didn't invent slang. Also "skibbidy rizz" is Gen Alpha more than Z. And slang very rarely is attributable to a single personality. Apparently Kai Cenat popularized "rizz", but it had existed for a long time before and has way outgrown him. The vast majority of people who unironically say "rizz" don't even know who he is.
The linguistic phenomenon isn't even linked to the internet particularly. It's just a contraction of "charisma", hardly an unusual way for slang to emerge pre-internet and not comparable to 1337 5p34k which never made it out of terminally online subcultures.

Before the internet, radio, TV, and the press were effective tools for massively spreading slang. Boomers had no issues making "cool" cool, as well as a bunch of other slang words that unlike "cool" aren't cool anymore.

Your generation had "WMDs" but I'm sure boomers had similar things with Vietnam, and their parents with WWII. Hell, in 1918 or so the entire world learned the phrase "Spanish flu" like we did "COVID". The more things change the more they stay the same.

And how can we forget "OK" whose origins are mysterious but generally people agree it comes from a short lived 19th century linguistic fad that gave "Oll Korrect" (what's for sure is that "okay" came after "OK"). Now "OK" is quite possibly the most universal word in existence. Sure back then it probably took a few years to spread within the anglosphere, but OTOH there was also much more dialectic variability in language across regions so it's not like there was less going on, it was just more fragmented.

People have always been going crazy with language and each generation appropriates their mother tongue in their unique way. The idea that language is even remotely static or "used to be less crazy" is entirely false, yet every generation perpetuates this idea when confronted with new slang they don't understand.