I’ve always wanted to include Sikhs in our armed forces; they make great fighters. And if they want their own distinctive uniform, then fine by me!
Why not Gurkhas?
Are are Gurkhas part of the Sikhs clan?
Every exception establishes a precedent. Once you set a precedent standards and traditions no longer have any meaning and can be discarded at will.
That's why we have an immigration nightmare. We kept expanding exceptions and set precedent.