I still think (and I've said it often, so forgive me if I've already repeated it here on this forum) that most people - at least in the US - don't really care if global warming is man-made or not. What people care about is how much it's going to personally cost them to fix in either direct costs or in terms of having to give up something they currently enjoy.
It also doesn't help that if one person sacrifices, it means almost nothing - it's kind of like immunizations. You need 95% of the population to take action to have any meaningful effect.
It's also annoying when as an individual you can reduce commuting, buy an electric car, whatever, and then you see a garbage truck belching black sooty smoke down the street, which just basically erased every action you took.
Part of it is that the mitigating technologies are more expensive today than their alternatives, with the idea that in the future costs will be lower - but that's a tough concept for most people. Just look at electric cars - they have an easily computable lower TCO compared to ICE, but their up-front costs for a comparable vehicle are higher - so people opt for the cheaper out-of-pocket cost even though the cumulative cost is higher. Heck, that happens with loans in general - "I can't afford $30k for a car, but I can afford 48 payments of $700!"
Also consider Tesla's powerwall - yeah it's got a really low $/kW-hr, but you still have to buy a lot of kW-hr - you can't buy $100 worth of powerwall, you can only buy $14k worth of powerwall.