The requirements from all auto makers, not only for ECU, but every single part is 10 Years/ 100k km for low end, 15 Years 150k km for high end. I think that is no secret. And that is 100% the experience if you buy a car, there is a point where the maintenance per year is more than the value of the car itself. At that point the car is effectively 0 EUR value.

I hear in USA the Toyotas hold much longer... I'm not sure why, if it is true, and what are the conditions.