The routing goes into the side of the steerer tube, that way you only need to change it if you change the bearings, to minimize the risk of that the top bearing is stainless. You can change spacers and stems as normal. Also not hard to swap from UK to EU brakes.
It is an XC focussed bike, not just for XC racers, just the same way that my Rallon is an enduro race bike but I don’t race enduro. Orbea describe it as an XC race weapon and not down country! It certainly looks like a fun light bike to me but I’ve certainly never considered XC racing!!
Dropper post isn’t limited by the frame, it’s Fox’s XC dropper with just 2 positions. Longer droppers are possible.
M30, the cheapest carbon version, is €4K, not sure what that is in the current pound.
Hope that helps a bit.