Who knows how people's subjective values get synchronized. It may not do you much good to try to understand the intricate mechanisms. So, if your fashion judgment is highly synchronized, that means you have a very reliable coolness meter built in. Take advantage of it. Synchronized is not identical.
Tastes certainly vary.
My point is people must have a lot of tastes in common . Every single subjective sense you have is shared by many others. Your coolness meter is a very reliable indicator of what lots of other people will think, just not all other people. Color schemes don't charm, so much as they make the people associated with them seem charming. Context overarches all.