Hello there
Personally I find the user interfaces intuitive, I think component manufacturers are more likely to provide a component library for altium because it's widely used by corporations & very popular with design engineers because they are very familiar with it. During a project & collaborating with other corporate engineers it's convenient for everyone to be on the same platform but then again Orcad, Candace,Pads it's not that much of a stretch. Some may argue that altium is the gold standard.