A bare trunk "will happen" when a pruning saw is used on the lower limbs- they're not going to just fall off on their own.
I would have been doing a couple of limbs each year in very early spring to train the tree along. Done early in the trees life the cuts become less visible but as long as you prune correctly you can limb up at any age.

See link below.
Please read enough to understand fully how and when to do this. Or hire it out. Likely it needs thinned a bit as well.

Here is a link that might be useful: Proper pruning techniques

Thanks for your advice. We are surrounded by wild trees/woods out here, so we rather expected these deciduous trees eventually lose their lower branches somehow on their own. Now that we know better, we can help it along when comes the proper season. Again - thanks.