He does not design anything at Magnepan.
This is false, Wendell does not take credit for designing anything at Magnepan but he is intimately involved with the design regardless.
It sounds to me like the OP would rather obsess over the shortcomings of someone who has worked tirelessly to promote what is a highly niche product that very few individuals I have met are even willing to consider taking the proper approach to implementing in the first place, than to realize that it's a miracle a brand like Magnepan is even still around given the plethora of available loudspeaker technologies out there.
Obsessing over things like why the crossover parts aren't different/better is just another reason why Magnepan has failed to reach a broader market. The product attracts hobbyists and tweakers who think they can take a $2,000 retail speaker and improve upon it instead of just looking at a better approach to their HiFi in the first place.
The issue with Magnepan isn't Wendell, it's Magnepan. Most affluent consumers of HiFi simply aren't interested in a speaker that looks like an obelisk from Kubrick's 2001: A Space Odyssey, requires a Hoover Dam to run properly, and need to be six feet away from a wall to sound any good in most rooms. The few that are, are few and far between.
If anything Wendell is the lifeblood that has kept that corner of the HiFi world alive and if you appreciate it (I certainly do) one might realize just how wacky one has to be to consider purchasing a system given the profile I've outlined above. I'm quite surprised they even sold 50 pairs of 30.7's if that is to be believed.