I don’t know any postmodernist who would disagree with you. As a matter of fact, even the anti-Modernists I know, this is their exact point. Truth is to be approached and held with humility, not used as power, especially because of the faith required. We must always be prepared to be wrong. And we should always examine for the possibility that we missed something we didn’t see before.
I think this may be true for sophisticated students of philosophy, but tends to be very un-true once this filters down to the WalMart Shopper level, where we see social constructionist thinking based on postmodernism leading to claims that gender isn’t biologically bimodal, for instance.
It’s a powerful tool for understanding thought, but when you wield that tool out in the real world, it can be used to basically make shit up.