This is a pointless question and years spent doing something does not make one a natural at it, or an expert. Ability cannot be measured in years spent doing something.
I’ve worked with people with 18+ years experience that are literally incompetent as designers and engineers, and I have taught students who after a 3 year degree are not only better than people who’ve done the same niche thing for decades, but also have excellent graphic design skills, etc. I would employ these graduates over certain “Design Managers” I have worked under.