Apparently, they do. For example, the white-tailed deer has a shoulder height of 1.0m to 1.1m, and that’s in the North. Towards the South, they get smaller.

I guess, that would be a general thing. Mainland US is relatively temperate. The real giant kinds of deer, like e.g. moose/elks, only really live in colder regions, which are further north (including in Alaska).