T. rex arm jokes

I came across a picture the other day that was a cartoony T. rex character trying to pick up a cup of water off a table to drink it, but couldn't because small arms, and I caught myself thinking it's an overrated, lazy joke. Which is a little odd, because I happen to find T. rex arm jokes hilarious and never get tired of them. This wasn't the first version that's made me think that, though, so what's the issue?

After some overthinking I've come to the conclusion that there's an easy way to miss the point of why, at least to me, T. rex having small arms and as a result difficulty doing some things is funny. Small arms or difficulty doing things aren't funny on their own, the joke needs the T. rex in it to work because the contrast is what's funny. Tyrannosaurus rex, the most iconic of dinosaurs, a huge, scary carnivore with big, sharp teeth and an unbelievable bite force, terrifying enough even millions of years after its extinction to be named "the king of tyrants"... has tiny, useless-looking arms. Badum-tss!

I mean, T. rex arms weren't even all that useless, they're considered to have been pretty strong for their relative size. They just couldn't be bigger because of the animal's massive head, or you'd end up with a creature so front-heavy it might as well be a quadruped. But it's the visuals that count there.

Making the rex cuter doesn't necessarily ruin it, it's still presumably a fierce beast by standards of cutesy dinosaurs. Anthropomorphizing the rex, on the other hand, kind of takes away the contrast. A T. rex who uses tables and cups and as I recall wears clothes, too, is bound to all kinds of boring conventions of human society - probably doesn't hunt and murder to eat, and instead buys its meat in neat little packages at the supermarket. What's funny about this creature not being able to do things?

The more humanlike you make the rex the easier it also starts to get for the punchline to accidentally be at the expense of actual humans unable to do some things. A joke about someone having difficulty with the seemingly simple task of picking up a cup and drinking from it isn't funny, it's just ableist. Even when keeping the rex as an animal, I wouldn't find the struggles with arm-related tasks funny if the species usually had no problem with those, and this individual just has had an injury or was born with smaller arms than usual. It's funny because the small arms are the standard for the species.

Phenomenal bone-crushing power vs. itty bitty forelimbs, that's the stuff.