The main difference is that PoS doesn't waste a bunch of electricity in doing so.
No, the main difference is that consensus is formed by those holding stake and not those willing to work. To me it is the difference between rent seekers (PoS) and innovators (PoW).
Yes, the main difference is that PoS doesn't waste a bunch of electricity in doing so. That is why government bureaucrats will force a change in a few years when more than $100 billion gets wasted.
No, with a PoS network we will exploit our natural resources faster than with a PoW network. That is my opinion and you may disagree; in the final analysis it really doesn't matter what either of us thinks.
What matters is how does one actually
force a change?
What you do is create a PoS "spin-off" from the bitcoin blockchain and try to legitimize it using your influence and economic power.
The market will decide whether is succeeds or fails.