While I agree with what you're saying, there are plenty of people who know a lot more than you and I who've only trained one style their whole life.
Knowing one style, and knowing inside out can be far better than knowing stuff from a bunch of different places. That doesn't mean it's always true, but it definitely does have its place.
While I've got a ton of respect for Michael Jae White's abilities, I don't get his mentality of what seems to be collecting black belts. Where's the depth of knowledge in 7-8 1st-2nd dans? If I had the amount of time in MA that he probably has, I'd rather a master's level knowledge in one art and decent level in a supplementary art; say 6th dan in karate and 2nd dan judo (8 dans total? Lol) rather than 8 dans total (
) in 7 different arts.
Everyone's got their own path. Choose wisely.