Collision avoidance, can be very hit and miss and on most cars I have had I have turned it off, usually a button or in the menu, as well as lane departure and off road mitigation.
On the golf we had the sun sometimes would even set it off, but putting your foot on the gas overided it, but on the civic we had next you could not override it and after a few times of a car behind almost crashing into us as the car did an emergency stop when you went to go around a car turning into a left turn.
I do on the motorway find lane keep assist very useful and I use adaptive cruise alot, couldn’t be in a car without it.
Not had mini so wouldn’t know, but sure you it must be able to deactivate it.