I won't even adress your confusion

What has physically changed in the whitetail deer? I'm unsure of any major changes in physical attributes. If there were only 1000 people in the united states...6' tall would be an accomplishment. Now you don't stand out in a crowd unless your 7' tall. Get my point. we see bigger better deer because we have more of them. As far as evolution....As soon as deer start growing camoflaged fur, than we'll talk. Until than

Same as it ever was!