People of Color

I don't consider people who are unwilling or incapable of self reflection and change to be capable of maturing (at least in any way that is helpful to communities and societies), and thereby don't constitute having achieved adulthood.

It makes sense if you think about how mean spirited preteens/teenagers can be and how many "adults" never really grow out of that. I consider these people to be "stunted" and/or "stuck" at a particular point in their self actualization where they were unable or unwilling to change their point of view because it made them feel bad about themselves or challenged their sense of self.

Instead of doing the hard work of growing up and reorienting their sense of self around a new paradigm (i.e. one based off of empathy for others of different races), they simply decided to ignore the uncomfortable possibility that they might be in the wrong, and were essentially lazy about challenging their own beliefs.

Again, not very mature, sounds a lot like a complaining angry teenager to me. And yeah, there are A LOT of people I would say are play acting as adults rather than actually being one. But that's just my not so humble opinion.