That's what it's called right? When a character is a caricature of what they used to be.
The only spongebob I've seen is the first 3 seasons and I've seen the movie like twice I think.
I still return to those first three seasons because even as an adult, I think they hold up and are funny.
I've seen clips on Youtube of more modern spongebob and it seemed like garbage, but I haven't seen enough to see how bad it is.
Patrick in this game, and I assume it's representative of how more modern spongebob is written, in particular is completely flanderized.
He was always really dumb, but in a funny way.
Here he's straight up retarded and is just like a caricature of how he was in the first 3 seasons.
All the writing and characters feel off, but his stands out the most, and I skip all the dialogue so mostly I'm hearing the quips Spongebob and Patrick make as you play the game.
You are correct on the definition of "flanderised." The little I know of Spongebob I learned from memes, but it's old enough that you might have people writing Spongebob who grew up on Spongebob, creating an exaggerated version because those are the memories that lasted to adulthood.