Transcendental arguments are traditionally used in response to skepticism. See Aristotle, Descartes, Kant, Strawson, Grayling, and Stern.
Transcendental argument in Van Til and Bahnsen is likewise a response to skepticism. They were not arguing for skepticism, they were arguing against it. It just so happens that the only answer to skepticism is the Christian worldview.
Presuppositional apologists often appear to argue for skepticism because their opponents attempt to respond to it through rationalist, empiricist, and pragmatic schools of thought. But it is unreasonable to assume, given the evidence, that any of these three general responses to skepticism really works.
Thus presuppositionalism is much more than mere worldview critique. It should not be primarily characterized by so-called negative apologetic argumentation.