Too high to be deer. Leaves on upper shoots (10’ up) stripped. Doesn’t look like insect damage as there are no partial leaves - they’re either intact or totally gone.
Squirrels come to mind
But mostly they prune off twigs
Deer have been known to get high leaves, bending down the branch and/or putting hooves on trunk. Your past recent deer problems are a sign they are very active in your area. Moose can sometimes get higher, I expect there are no moose where you are though… Squirrels generally don’t eat leaves. Its hard for any animal to get to the tips if they are not a big animal, if they walk along it the twig will bend too much.
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Possible, but l get a pic. Doesn’t look right for deer. Especially since the lower leaves on these two trees are untouched.
umm. . . a tornado? 
Squirrels are known to strip green material for nest-building. What volume of leaves are missing?
Some years I’ve had ‘forest tent caterpillars’ totally defoliate young oaks in my plantings…overnight - and sometimes, again, after re’leafing. And it’s amazingly difficult to catch them in the act.
I found large brown beetles. They look like May beetle/Junebug, but it seems a bit early for those.
One small branch at the top was stripped.
There are beetles that show up early, I used to have problems with these little early beetles on my apples. They are not what you have though as they are slow and leave lots of partial damage.
I had some kind of large, horned caterpillar that was eating apple leaves at an alarming rate; seems to me they left the stems, though. They were active in the day time and easy to pick off.
Oaks are a favorite of gypsy moth caterpillars. Older/larger GM cats feed at night
Sounds like an insect is munching all the leaves. The very hungry caterpillar…