Australia

There is a very good reason to turn off traction control on public roads, it's terrible on dirt.

I grew up at the end of a small but public dirt road. My partner has a prius that's good for the drive from Sydney home so we often use that when visiting. There are two steep hills on the gravel road. If traction control is on it cuts power as soon as a tire starts slipping, so I go through an annoying sequence to turn it off every time we enter or leave the farm and then it can do those hills easily.

My big concern with rules like this is if they then push to make it so manufacturers don't add a traction control button or at least some ability to disable it. They should just be punishing the actually problematic driving (drifting on public roads) instead of making it illegal to turn off traction/stability control.

ABS and AEB make more sense to require on, although I'd be somewhat worried in older cars that a fault in that system would turn the car into scrap if you couldn't get the parts anymore.