According to Osho, yes—any influence borrowed from an external medium will inevitably wane once you disconnect; that is the nature of influence. Only what has awakened within you endures. A medium may trigger an inner flowering, but once it becomes your own, it remains. Your inner wealth doesn’t diminish, and evolution of consciousness cannot go backwards.
If you stop relying on something outside, its pull fades; what you truly grow inside stays and you can’t un-grow it.