I suspect the EU is trying to "enforce demand" for a few reasons. Individually I feel people have a bias towards checking the features and price of the phone they are buying right now and not so much resale value or if it will last 4+ years.

But the EU thinks society will benefit from less electronic waste and more durable devices. Or at least EUropean society, which AFAIK leans towards importing smartphones rather than making or design them. And this is far from the first time governments enforce features on products that the market doesn't seem to be demanding.

But is the EU thinking of something about enforcing longer software updates timelines? I suspect this law won't be so effective without it.