We did that on a young Copper Beech on the advice of our tree surgeon - he told us to imagine what shape we wanted the tree to be in 10 years' time, so we took off all the small shoots to allow the trunk to develop, with a canopy, rather than become a shrub in poor shape.

All I would add to this is that leaving lower branches will encourage the trunk to thicken quicker than if you "lollipop" it now so don't be too enthusiastic with your pruning just yet!. Perhaps leave the upper half intact and only remove a branch or two from the base every second year. If you remove too many branches, you will lose vigour defeating the object. It has to be balanced.