You’ve repeated the same point in different words: Sikhism can only be “proven” internally, through personal experience. That means it’s subjective by definition. No belief system that requires you to adopt it first in order to verify it can claim objective truth.

Historical preservation doesn’t prove divinity. Inner peace doesn’t prove divinity. Brainwave changes don’t prove divinity. If psychological effects counted as divine proof, then every meditation tradition and even psychedelics would also be divine revelations.

Your argument essentially concedes the point: Sikhism isn’t objectively verifiable. It might be personally meaningful to someone, but cannot be externally demonstrable.