I’m not sure what was going on, I’m hoping it was just tired. I have some stray cats in the neighborhood so I managed to grab it and look it over (I’ve got a zoology degree, and used to be a zookeeper, I don’t usually try to handle wildlife but wanted to make sure it was okay). I put it up in a nearby tree to get it off the ground. It flew higher up into the tree, and was gone about an hour later when I went to check on it.

Many birds feet curl by default and need effort to flatten. It keeps them perched while sleeping.

I think it might have a curled toe deformity. I know for domestic birds they splint the feet to correct it, not sure what happens in wild birds though.

Baby feet are like curled canned shrimp.