I would suggest that strict asceticism is an extreme way to live. Really I would suggest that all ways of living are extreme, the only difference is the extent to which one fully recognizes and benefits from the profundity of life's experiences. But in this view, what's the difference between doing nothing and mountain climbing? I don't see how Evola's actions and experiences can be interpreted as hollow unless their nature is examined to a very deep degree, in which case what's at issue is not so much these actions and experiences per se as much as that which is at the heart of each one of them--Evola himself. He was living an extreme life, the question is to what extent he realized it, and to what extent he conveyed this realization, keeping in mind that such type of realization often gets confused with the simplicity of the mundane.
I don't know anything about this author or traditionalism, but I'm guessing Evola's fault is that he assumes the path he's realized is applicable to all people, which is rubbish.
Just to clarify, then:
Traditionalism is the idea that there is a supra-historical level of reality, of Being so to speak, which has been conveyed by generations of civilization in various forms, i.e., Tradition. Or so is the definition as Julius Evola and Rene Guenon would put it. The source of this can be identified, for example, in say works like The Bhagavad Gita, The Upanishads, the original Buddhist Pali Canon, works by Plato and the Neoplatonists, Zoroaster, Mithraic and Hermetic texts, Grail Romances, and so forth. The forms of Tradition are generally best exemplified in esoteric traditions of religion, which generally tend to take the form of either asceticism of action (Kshatriya/Samurai/Knight errant, etc. i.e. warrior tradition, but also including ceremonial magick), and asceticism of contemplation (yoga/meditation, etc.). Essentially, these practices are meant to bring those who have the potential into a level of supra-humanity, where they then become a Divine principle manifested on the physical plane (world of manifested forms vs. the unconditioned). Rome was also an example of such a Traditional civilization, the hallmarks of which are an orientation towards that which is "above". Essentially, it is a very tangible concept of seeing Reality as it is, and coming to the point where one is "Lord of the Chariot of 5 Horses", and to whom Being is an essential component of one's nature from then on, as opposed to a frantic and feverish Becoming. This is not however, to be equated with stagnation.
Now, via this definition, wahn's point was not that Evola's experiences were at all hollow, but rather he never reached true knowledge of this state of reality through his practices, therefore, in his argument, somewhat invalidating the entire concept of traditionalism (at least via Evola).
It is important to simply note that there are levels of this philosophy as well. On one hand, practices like Hermeticism were dubbed "The Royal Art" by Evola because of the caste that would naturally have the potential to practice this. Evola was not arguing that all people have the potential to become supra-human, but he did believe that the hierarchy of a traditionally oriented society gave the rest of the civilization the ability to participate in this level of reality to a greater extent than otherwise might be, and thus elucidate meaning in the lives of those who are not the rulers through whatever medium their natures were best suited to. That was the idea of his political writings such as Revolt Against the Modern World and Men Among the Ruins. Conveyed into the much decayed modern realm, it is the idea politically that the best shall rule, but it does put some additional qualifiers on what that elitism means, essentially asking for qualities in an aristocracy that are transcendental; in particular, the quality of seeing reality beyond the merely physical.