Q.My Sycamore Tree Doesn’t Leaf Out Like It Should, I Don’t Think It’s Root Rot, Could Pruning It Help Bring It Back
not moist enough for root rot, not many pests either, but I know it’s been many years since it was pruned last

Certified GKH Gardening Expert
Unfortunately your photos did not come through. Unfortunately, this does sound like a root rot issue, though.
You can try pruning for shape, but it will not likely correct your issue. In fact, depending on the disease, pruning could make it worse.
You can contact your local extension service for help in sampling for disease or soil nutrient deficiency. This link will help you to find the closest to you.
https://www.gardeningknowhow.com/extension-search/
https://www.gardeningknowhow.com/ornamental/trees/sycamore/sycamore-tree-pruning.htm