To be fair, the Hubitat founding was predominantly devs that got tired of SmartThings and decided to go their own route. If I had to hazard a guess, most of their experience was probably in backend app coding and not on UX design. Now they're a small company with (what I imagine) is probably not a huge revenue stream. Hence, we get a pretty solid functioning hub with a, admittedly lackluster, UI.
So, what do they do? I can't imagine they have the budget right now to bring on a full-time UX designer. They can opt to contract out having someone come in for a few months to refresh the current UI, but then the existing staff would have to learn how to maintain and build on it once that person is gone.
My hope, and probably the same for others, is that the added revenue of the C-8 launch in tandem with Wink and SmartThings users jumping ship will help open up the full-time option.