Silver Rank always increases and decreases.

I have always have been the max Competitive Skill of Silver in any playlist for Arena. It always increases and decreases. I know I will never ever get Diamond, Gold, Platinum or Onyx because I am too stupid to do so. Does my profile disallows me to get any playlist rank better than Silver?

No. It just means that you lacked the wins needed to place gold / promote from silver

Silver 6 is the highest for silver btw in case u didint know