Sikh's carrying a knife, a bracelet, a comb, etc. has never bothered me in the slightest in all the decades I've known about this - the Khalistan movement in a particular location during a particular time aside, they're not exactly actual postcards for terrorism (despite what some might think when faced with people and turbans).

They always had a pass here in Australia for many years until things tightened up.

Not that I'm a fan, but in general Rules are Rules and making exceptions while fair in some senses will be unfair in others <shrug>.

Circling back to my initial comment- it is the case that there is an actual reason rather than a made up bit of bullshit, to reasonably suspect that a Sikh might be carrying a knife ... if they are they're almost certain to also have a comb .. so that's handy.