See post #13.
The onus is still on the insurer to prove that the switching off or tampering with the ADAS was directly responsible for the claim.
Anyway, it’s all very simple for everyone. Buy your vehicle, but don’t then go tampering with the ADAS system or start ‘chipping it up, mate’ (or whatever the term is) and all will be well. If you feel you really must, then inform your insurer as to what you’ve done or intend to do. You might need to talk to someone above the level of chimp, but hey, that’s life.