A law requiring a particular material? Unless it’s health or safety related, no way. The last place I want to see government is regulating how a product must be constructed (unless it’s health or safety critical obviously.)
If you want a device without plastic screw holes, pay more money and find one or make one yourself, market it and sell it to other like-minded people.
If I have a toaster that breaks, the time it would take me to go to a repair shop is more valuable to me than the cost of a new toaster – not to mention the cost of the repair itself.
In China, you often do get smaller appliances repaired because the labor cost is so low. So it makes economic sense to get those kinds of items repaired.
But in France, if I want to get a microwave fixed, the item is either still under warranty or the depreciated value is less than the repair cost. Perhaps if government lowered taxes and relaxed the labor code, then repair shops could charge less and it would incentivize people to get repairs on smaller ticket items rather than buying replacements. But I certainly am not going to spend €65 getting a €150 microwave repaired when the microwave is already several years old. I migh spend €20 for that repair if I really liked the microwave.
I certainly wouldn’t be happy if I had to pay several hundred euros more for a microwave because of a law mandating the type of screw holes that must be used. The increase cost wouldn’t even be in materials as much as the buereaucratic cost of implementing such requirements.
Health and safety regulations – of course. Regulations because you’re unhappy with screw holes? Not a chance.