Drones don't conquer areas. Drones don't search for explosives or hidden defenders. So no, this will not change the number of soldiers but just be an andditional wave before them taking over the job that precision-guided artillery is fullfilling now.
Also there are only very few situations where a new type of weapon actually replaced older ones. Not without decades and decades of the existing ones being adapted to new tech and tactics.
Your "we don't need forward deployments other than limited air defense anymore"-argument is the same wrong simplification we heard about the end of tanks after every single bigger engagement since ww1.