The biggest bad and reason why I will never own one is proprietary crap. A $2000 bike should not have special stems, handlebars, and even stupid headset spacers.
I agree, it is a PITA. But to be fair, everyone in the $4000+ price range has stuff like that. Its just that Canon gives you a $4000 bike for $2000. I wanted to get a used Specialized, but had to buy specialized only wheels. Trek, Specialized, Cannondale all do that kind of stuff - and it hurts when they do it on all their bikes. Really, its been an issue with the industry as a whole forever, and it just getting worse as standards splinter.
Just like the old engineering saying: "My implementation of standards is better than your implementation, and i have the customizations to prove it!"
But Canyon have plenty of mainstream builds and parts in their non high end bikes. You can have it either way.