Maximize fence post distance for wooden fence?
Since your landscaper is concerned with wind, I am going to assume you are putting in a privacy fence. In that case, the height could dictate the spacing, if you are willing to put in a lower fence then you could increase post spacing, but 8ft spacing is typical. Also, the lower your fence the less deep the holes would need to be.

Another thing to consider is installation method, if professionals are installing your fence, then they may use an auger to drill the holes, which may damage your tree. However if they are truly professionals, then for the 2 posts closest to the tree, they could use a manual post hole digger, and dig as narrow a hole possible to minimize effect on the tree.

Lastly, if you were to consider another fence type such as a picket fence with narrow pickets, then you could minimize wind loading and increase post spacing.