What a load of bullshit. Everyone says it's a fundamental change, everyone but those who've made some changes to their lives and found it to be almost embarassingly easy.
Wanna make a change? Buy less clothes, buy less shit you don't need, eat less meat, eat your leftovers, stop throwing away food, walk more, get a bike, stop getting holiday houses, stop going on vacations around the world all the time. If just a 100, then a 1000 then a million and so forth did this it would have an enormous impact, and it takes so stupidly little effort to do it. It's not hard. It's easy. You don't need to have a PHD in the universe and everything in it to make these changes. All you have to do is be an adult and stop making excuses. Speaking generally of course.