What critter would do this?

Squirrels, chipmunks, mice, moles...

I'm guessing voles. Some years their population explodes and in winter they forage under the snow and eat bark, living or dead. Last year they killed about 1/2 an acre of young trees beside my place by eating all the bark about 6" up.

Mice . . . or a chupacabra maybe? My money is on mice . . . see this with wood on the ground left over the winter under the snow.

Rabbits also love fruit tree bark. I consider maple among the fruit trees since it has edible parts. I used to raise rabbits and gave them apple tree prunings. They chewed the bark right off.

I associate missing bark with really heavy snow cover. When the ground is covered from first snowfall to late spring melt.
I just picked up some deer bones. Whatever doesn't hibernate in the winter. If mice can eat the shed antlers of deer, then they and all their little frennies can eat everything else. I did catch deer up on their hind legs reaching for leaf buds. I also saw them eating bark. I always thought it was rabbits, though.
Rats, meadow voles, field mice, rabbits, deer...

Apple tree limbs below the snow line.

Deer were eating the bark off the trees there.

It was a bad winter for animals.

We get exactly the same as the OP photos and it's almost always deer.