Pop culture references in cartoons worked 50, 60, 80 years ago when very little was likely to change between the time a cartoon went into production and the time it was released. When production of "Hollywood Steps Out" started in 1940 the animators could be reasonably certain that celebrities like Clark Gable, Bing Crosby, Mickey Rooney, Cesar Romero, Rita Hayworth, The Stooges, etc would still be fucking news when the short came out in '41, and indeed most of them were still relevant and very little of Hollywood celebrity culture had changed when the short was re-released in '48.
But memes in the internet age work different, 99% of them don't have any real staying power - they enjoy their five minutes in the spotlight and then they're quickly replaced and forgotten. Which is why it comes off as so cringey and dated when animated shows try to work "recent" memes into their content like when Futurama built an entire episode around a Susan Boyle pun two and a half years after Britain's Got Talent.
Chungus had it's five minutes of fame... in 2018. Trying to capitalize on it in 2021 just shows how completely out of touch network executives are.