Uh oh, I think "now-reformed copyright law from the 1970s" is my new hyperfixation!
I've been compiling a list of cartoon characters that would've been public domain by now if copyright wasn't reformed in the 70s (it was previously 56 years), and it's honestly an outright tragedy - pretty much everything notable from Looney Tunes, Jay Ward, Osamu Tezuka, MGM, The Beano/Dandy, UPA, or Dr. Suess; all the European cartoons like Smurfs/Asterix/Lucky Luke/Tintin, Thomas the Tank Engine, a handful of Muppets, Alvin and the Chipmunks, a good chunk of the Marvel and DC A-Listers, and a half or so of the classic Hanna Barbera lineup - not just that, but we'd be less than a decade away from Scooby-Doo; Wacky Races; Fat Albert; the earliest version of Garfield; and the first video games. Sonic and The Simpsons would become public domain before most of us would gain a single grey hair.
Not just that, but pre-reform copyright law required manual extensions on the 28th anniversary (which is why some Bugs Bunny, Mickey Mouse, and Popeye cartoons are public domain, but not the characters themselves) - so a ton of dead/failed IPs from the 80s and 90s would likely be in our grasp by now. Who doesn't want to revive the ever-beloved Shnookums and Meat?