My non-scientific answer.
Cooking via the reverse sear method doesn't result in a classic looking well done steak. Temperature wise, you're well done. But because those temps were achieved mostly in indirect heat, the meat does not turn brown all the way through. With a direct cook to well done temps, the outside is actually a higher temp and more done than the middle when it achieves the well done temp.
What I've done for family members that want a well done steak is cook indirect to a lower temp, then finish it off over direct heat longer than the mediums. This gives the classic well done look to the meat while still being more tender than a well done steak cooked over direct heat. I've spoiled a few of them doing this:)
I've also overdone steaks in this same manor by accident and given them to people who like mediums and they don't complain (too much) about the taste and texture, just the color.