Q.Rose of Sharon Tree
Last year my Rose of Sharon came out in full bloom beautifully. This year no greenery or anything, just a grey looking tree. You think it’s dead?

Bend the branches; do they snap and break off?
If the branches break, this part of the plant has died.
You can also scratch the bark to determine if the shrub is still alive.
If you see green, that is still alive.
Here is a link that explains this test.
https://www.gardeningknowhow.com/ornamental/trees/tgen/tree-scratch-test.htm
Plants can die for a variety of reason, and many times it can't be explained.
Here is a link to refresh you on the care requirements.
https://www.gardeningknowhow.com/ornamental/shrubs/rose-of-sharon/rose-of-sharon-bush.htm