Yeah, I couldn't imagine MLP working in live-action, but I was just saying some stuff does, so not all live-action adaptations are bad.
As a kid, I loved the Flintstones '90s movie, and John Goodman was definitely the perfect Fred. They made it feel more like the original cornball classic animated family sitcom, then just a movie, which is why I loved it. The set designs, cartoony sound effects, and dinosaur puppet designs helped give it a more cartoonier atmosphere. (And they kept the modernized vulgar humor to a minimum, unlike some modern movie adaptations that try to make 'em too edgy. Though, I'll admit,
Deeno was adorable too, and I like how they sneakily reused Mel Blanc's sounds for him.
I also liked the 2000s "Rocky & Bullwinkle" movie as the main characters felt very in-character throughout it, kept the puns, and the meta self-deprecational humor of the original cartoon, while also poking fun at all the tropes of "animation turned live-action movie," as well. Only problem with it was it needed more of Jonathan Winters.
The problem with other animated-turned-live-action movies is they usually try to make them too realistic, too modern, too vulgar, too dark, too meta, too serious, too goofy, or too something. A common problem is especially focusing too much on the "new normal human" characters sometimes. (Like the '80s "Masters of the Universe" movie, or the live-action Transformers movies.) Luckily, the Sonic movie still focused on Sonic, and his one-liners.