My understanding of the Montreal protocol is not that corporations decided to follow regulations from their good hearts, but that they managed to play the clock long enough to have better and cheaper alternatives anyway [1].)

That being said, of course I do believe regulation help - but, slowly, reluctantly, and with every interest fighting tooth and nails.

Therefore, I'm still shocked that a regulation would be _that_ successful (75% reduction of anything in two years is unbelievable.)

However, if insurers are more powerful than activist, that should give some ideas. How can you make premiums for fossil fuels plants get so high that no insurer would touch them ?

[1] https://en.wikipedia.org/wiki/Montreal_Protocol?wprov=sfla1