Because technology progresses faster than laws and by the time the laws catch up there are already powerful corporations established based on the lack of those laws.
For example its an obvious public and environmental benefit to require that all phones have a user replaceable battery but until recently they almost all did and now it's too late because every phone maker would lobby against it.
It's not difficult to fix. It's just that corporations want you to throw out and buy a new phone every year. This is what happens when you let the same company make the software and the hardware.
For the last point I saw that to heat the oceans as fast as we are it would take a nuclear bomb worth of energy set off every second for the last few decades.
I doubt it. My new gpu released in 2019 is 3x as powerful as my 2013 gpu but the new CPUs are mostly only improved in core counts.
Rendering is also an insanly parallelizable task. In the worst case we can always slap 2 of the same gpu on one card and get them to render half the screen or for vr, one gpu per eye.
It would be cool but they haven't done it and we don't have time to sit and wait. If we start self enforcing these rules on ourself then when it comes to election time people will be more open to voting for a government that does this.
Every time I have seen a feature that was written general to handle possible future uses, after a year of sitting unused there will certainly be modifications or surrounding code that doesn't support the planned extensibility. So it can never be used without a lot of work changing things anyway.