Maple not fully leafing out
The late season freeze-hail-freeze has caused trees to struggle. As trees leaf out in the spring, late freezes can severely damage or kill buds and new leaves. This will cause a tree to use stored energy to re-leaf so this can result in a slower second try, or fewer/sparser leaves.
It's a good sign the branches are flexible and not brittle. You can also take a sharp knife or use a fingernail to gently scrape a small piece of bark off of several small twigs. If the exposed twig is green, the branch is still alive. It appears in the photo that the tree has many buds on it, some quite large perhaps nearing leaf out. Take a close look at the buds to see if they are green (alive) or black (dead).
Take a wait-and-see approach for the tree. Make sure the tree receives adequate moisture and look for growth.