I don't object to anybody's perceptions... but the way to solve them is to "bring them too the mats" and test them out. "Altitude adjusts a lot of attitudes"...
I've seen a lot of skepticism go out the window as the skeptic came crashing to the mats or got his lights knocked out. It's hard to block a good right hook with an argument.
While there's a mental aspect to martial arts, in the end, they are physical skills... whether manifested using "training", chi, or whatever, and highly connected to good body mechanics. Skepticism can't block a good Uchi mata, or shiho nage... and the trip to the floor for the skeptic is usually a real "eye opening" experience.
Be skeptical if you like, just don't whine when you get slammed.