There are many better models out there than ones from Fender and Gibson, but we are creatures of habit and marketing. I believe most of it is down our Six String playing friends, they very rarely stray away from what's available in a local shop meaning anything else isn't "cool"
Yamaha, Sandberg and PRS have refined their own designs and are probably technically better than a Fender or Gibson, but since they only get a fraction of market share they aren't going to get in as many hands to understand the differences.