i'm got a bit confused with the premise of this comment. i'd say otherwise about Blender. the UI isn't bad because of being Free or because of the target audience, it is because it lacks people to actually design and maintain a solution. consider that projects like Blender are massive, with several companies offering funds and others relying on it for some jobs, so they have all the incentive to hire people specifically dedicated to UI/UX design. that is in contrast to a side-project built on top of an API from a corp who was very much happy to see them gone.

that said, i don't know Sync enough to judge the argument considering that project, but the impression i got is that Sync also has a stabilished incentive to give specific focus on making the UI easy for any new user. Sync being proprietary doesn't matter in this case.