There is also another point that I forgot, and that is a main point of the french fine I think.

In itself, if explicitly warned and controlled by the user, throttling to work better with an old battery would not be so bad.

But the thing is that, if your phone (or laptop) does not last long anymore on battery before shutting down, but otherwise works normally, you know that it is just the battery that is dead and that needs to be replaced.

But, if the phone becomes slower/sluggish, most non tech users will think "my phone is slow because it is old, it's normal aging, so I need to change it with a new one".

And worse, some will even think that their memory was wrong and that it is just that the new models are so fast and reactive that they realize how slow was their previous phone without them realizing.

This makes me think about the case of Windows. It is well known that a computer with Windows will go slower and slower time after time as the system get messy. Based on that, I can't count the number of persons that I have met that were thinking of changing their computer for a new one because the old one "became slow because of its age". When the real solution was simply to reinstall Windows to have a fresh system!