Imagine a fundamentalist violin . All it plays would be fundamental tones similar to a $20 Casio keyboard. yuck

Imagine a ruling fundamentalist government. It may deem ancient ruins or statues sacreligious and destroy them , not because there is a fundamental teaching to do so but because they have the intimidating power to do so.

Fundamentally the foundation of fundamenatalism is based on a fundamental truth known to all parent child relationships - which is " Because I Said So" ;-)
It always comes down to some guy dictating to an individual or group that it is his way or the highway (or worse). Pointing to a document ,no matter how old , for legitimacy does not make it so.