"It's kind of crazy that bikes are designed by riders riding trails in Marin or California and then they're expected to perform as just well as bikes designed for a very different set of trails in Western BC."
I would assume riders who are into MTBs would take into consideration where the folks designing the bikes ride and what their interests are. I have nothing against people riding flow trails and designing bikes for them. As long as I don't have to ride 'em or ride the bikes designed for 'em.
With that in mind I don't think thoughtful people expect a specific bike to work everywhere equally well.