This is interesting to me! I've never met an engineer or artist who I would trust to do the UX. They are very, very disparate skill sets with very, very different goals. And, all the "hybrids" I know understand where their limits are, and we often work very well together on the nitty-gritty details of interaction design, like the precise timing of transitions and such, but they're generally more than happy to let me do the bulk of the UX work, figuring out all the edge cases and flows off the happy path.
But, I do have a theory that if the entire team understands the user goals and how the product is supposed to best support them, and everyone has a modicum of good taste, that maybe you don't need dedicated UX people.
Maybe you can workshop the entire UI and flow, like in a design studio. Maybe you need a short-term UX person to facilitate; maybe that can be taken on by a manager, or it can be a role that's rotated through.