Any solution to a problem that starts 'If everyone did ...' is the deadest of expired ducks.

Global ecosystem collapse is a systems issue of vast complexity. While we need at a minimum to (1) take down capitalism and (2) explore social and 'economic' (scare quotes intended) alternatives, no-one really knows how to do these things. They're certainly far beyond my capacities to contemplate. This has little to do with 'fossil fuel companies'.