If what they trimmed represents a good amount of the cover, then yes this may have been a factor. Years back the county took out about that much of the trees along our road years back and the deer then stayed out of that area cause significant thick roadside cover was gone. Just the commotion and sound of machinery will not spook them out permanently - in fact that type of activity with chain saws and other machinery roughing up the earth has been known to draw deer into an area out of curiosity. If you still have the cover to hold them, try some scent attractants to bring them back. Commercial attractants or even vanilla extract.