Fun fact, trying to determine if a dog is more intelligent than a cat is nearly impossible because that it's hard to tell if the cat doesn't understand the test or just can't be bothered.
The cat understand perfectly the test, but think that, if you like it so much, leave me alone and do it yourself. A dog is a pack animal and for this reason it obeys, yes or yes, the leader of the pack, the owner, a cat or felines in general, with the exception of lions, they are solitary hunters and do not have the concept of a leader, A cat sees you as an equal, at most a friend, but not as a leader. This has nothing to do with intelligence, but with the very nature of these animals.
Cats just require a different approach. But it's far from impossible to train them as long as you adapt, just as you would for any various species of animal. This guy has figured out how to train cats and he's hardly the only one.
Lots of cats big and small are very social, even if they don't form packs in the wild.
Yes, cats can form groups when this offers them advantages in food and survival, as is frequently seen in stray cats, but they are anarchic groups, without fixed leadership. Naturally you can train cats, but only if they see an advantage in following what they have learned, they must be convinced to follow your instructions, which is much more complicated than in the case of dogs.
It depends. If the toddler is trying to actively kill themselves, they are super smart AND fast. On the other hand, I'm told that some cats share a braincell, and if it's not their turn with it, then that's that.