It’s because their wiring system basically just daisy chains everything together with network cable

That's the case in all modern cars beginning in the 90s: Everything that's not directly mechanical is on the CAN bus. Not every single button individually, but button assemblies (the steering wheel counts as one), there's no wire going just for the blinkers through the wiring harness it's connected to the same bus that also carries signals for the brake lights.

Capacitive buttons are simply cheaper than mechanical ones, also, too many automotive designers seem to have no concept of haptics and UX they're in it for the sleek curves. Or, well, no concept of haptics that isn't about how satisfying the door closes, they still get that one right.