I mean sometimes you have to cut the cables to get them out of the frame if they're internally routed due to the olive or whatever the press fit chunky bit at the end is called
This is why I started to look in the direction of steel bikes because those seem to be the only ones that still have all things external routing for ease of life.
cables are just as much of a ball ache to route internally- that's a frameset issue, nothing to due with what runs within the hose.
Also you don't need a bleed kit to swap or even install hydro discs assuming they are already bled. One 8mm spanner is all that's needed.