It's not entirely invalid, however the Big 5 (OCEAN) model is robust and offers certain predictability, e.g. political affiliation. This is a huge topic that warrants definition of terms starting with the definition of "you" which immediately complicates things because when people typically say "you" or "me", they have a lot of assumptions and societal conditioning baked into the meaning they're attempting to convey. This topic also gets right up next to the astrology conversation which is rooted in physics principles like the electromagnetic right hand rule, rhythm entrainment of oscillators, and constructive and destructive interference patterns.