I’m from Poland and I own 3 Canyon bikes: Canyon Ultimate CF SL, Endurace AL and Grail AL with GRX option. So far so good. Great bikes, race ready, fully equipped, with no cheap components that ruin all the build. And I have same comparison: Argon18 Gallium Pro (twice as expensive as the Ultimate CF) and Specialized Tarmac SL6 Pro (the same story with the price). No problem with servicing here in Poland. Actually, LBSes like those bikes.
One think you have to note is the steering tube dimension. 1 and 1/4 inch is the Canyon standard. So, you have limited options to change a stem or a integrated cockpit. And, from my point of view, the only disadvantage of those bikes is readiness for only one type of groupset: electronic or mechanical. But, same say that this is a big advantage for them: no extra holes in the frame when you buy the mechanical option.