What I find particularly bizarre about this topic in tying it to mysticism is to say that the mysticism's goal is to make a new religion, a "one world religion" on top of it. Nothing could be further from the truth. What lies at the heart of the mystical experience is the ultimate transcending of one's own religion, in fact the transcending all religions. It is the exact opposite of forming a new religion.
What mysticism is able to do is to preserve the unique qualities of each religion, to respect the differences, while at the same time being able to see one another beyond the religious labels we all wear, to see beyond what divides and embrace what unities. This is not some imagined new "one world religion". It's simply realizing we are more than the labels we apply to ourselves and see each other not as enemies of one another, but spiritual brothers and sisters together, each within our own respective cultures, or religious, or nonreligious contexts. It recognizes the relative nature of these things, as well as their importance to each person. It unites through a unitive consciousness, as opposed to divide through an exclusive mind that focuses on the differences and shouts, "You're not like us!". The latter is the ego-mind trying to find itself by external identifiers, that which marks differences between themselves and others. The former is an inclusive mind which sees all as being more than our differences and embrace one another in that which transcends all boundaries.
It is in fact the exact opposite that is the truth. It is not the mystic who seeks to make all world religions one. It is the fundamentalist who does. The fundamentalist seeks to destroy all other religions, all differences, and make their own the dominant world force to control what is believed and practiced. That is in fact the very reality of it. That is why the fundamentalist despises the mystic. The mystic removes such aspirations, valuing differences. The fundamentalist despises differences and seeks uniformity through their elimination. The mystic seeks unity while preserving differences. If we want to put mythological faces upon this, the mystic heart is the heart of God bringing and holding all together in their infinite array of diversity into a unity within One Heart, whereas the fundamentalist is the mind of Satan seeking to destroy unity through division, imposing itself, its own image upon others to make the world one it is own image. The one seeking a "one world religion" is not the mystic, but the fundamentalist.