No, they really were (hilariously) dumb and simple. Of the top of my head I remember their capital was named “Big Strong City”, their “Red Alert” was “Red Alarm” (it’s funny in context) and they didn’t really understand that’s an emergency, and despite being corrected multiple times by the woman herself, they kept thinking captain Carol Freeman was captain Kathryn Janeway. For reference, one of them in black and the other is white.
No, they really were (hilariously) dumb and simple. Now let me list two examples that are just vocabulary.
The Pakleds weren’t as dumb as they pretended.
Yeah Lower Decks played on their stupidity. But everything about Lower Decks was an exaggerated form of cannon.
But the actual behaviour of the Pakleds was to mislead people into thinking they were harmless through playing on their own stupidity.
Now I’m not saying they were a smart race comparable to (for example) the Romulans. But they weren’t as stupid as they portrayed themselves.