I regret to inform you that, upon experimentation, not every 2000s Disney Channel original series holds up as an adult. The good news is, That's So Raven is one of the exceptions.
Watching the series again recently, I was surprised to discover that I had not only seen most if not all the episodes as a kid; I also remembered most of them down to the jokes. The series was groundbreaking in a lot of ways as it aired, and was also ahead of its time in its focus on incorporating "controversial" topics into its storylines. I knew what racism was when I saw that episode as a kid, but it was the first time I'd seen a show that asked me to really think about what that really meant and how it impacted real people around me.
There's really only one element of the show that bothered me watching it again all these years later, and I'm not alone in this complaint: The writers really took an interesting female character, Chelsea, and reduced her to a boring, "cringe" stereotype. Her character, by the end of the show, basically becomes nothing more than a running joke rather than a person with her own storylines and growth.
I don't think I picked up on this as much as a kid, but her character in the show's first season is smart, compassionate, and a pretty decent friend. The further the show progresses, the more Chelsea becomes a one-dimensional punching bag. At the start of Season 3, Eddie even starts to treat her like an annoying sidekick he can't bear to get rid of. They must have even directed her to "talk dumber," which really picks up in Season 3. Every other character starts to talk down to her like they're embarrassed to have her around, and that gave me the ick. I haven't stopped thinking about it.
It's not an uncommon trope even in modern comedy to have at least one character whose intelligence -- or implied lack thereof -- is played up for laughs. But That's So Raven's writing and physical comedy was good, especially in the first season, without having to put Chelsea in the position to be laughed at, not with. This trope is especially off-putting when it's applied to female characters -- especially if said character didn't start out being written that way. How can we make this show funnier? Make one of the girls dumber! Raven didn't make a lot of mistakes, but this one really stands out in the worst possible way.
It still surprises me that in a show so progressive for its time, it felt the need to sacrifice one of its characters for the sake of added comedy. At least they picked one of the few white characters on the show to dumb down in later seasons? Still not great, though it could have been worse. I haven't seen Raven's Home yet, but maybe they gave Chelsea a chance to shine a little bit in that one where warranted. Even in a near-perfect show, you're not going to get everything right. But I'll never forgive them for one of the few things they did get very wrong.