I think it's mostly tribalism and fear.
For everyone, to some extent, belief is social. You tend to believe what your in-group believes. If your in-group is big on science and admitting fault and such, it's not so bad. But if your beliefs are... I'm too tired to be nice... Right wing dog shit ahistorical afactual nonsense.. then you're in a worse place as far as having beliefs that match reality goes.
Secondly, fear. Admitting climate change and pollution exist means admitting uncomfortable truths. It means admitting things need to change, that the future may be from, and you have some culpability in the current state. The way things are now is familiar and comforting. Most people are, frankly, cowards, and will go to great lengths to avoid this kind of fear. Especially if it involves them not being a completely faultless person.
The longer you go being a denialist, I imagine the harder it is to change. Admitting fault isn't something most people do well. Again, because they are on some fundamental level cowards. Many people are deeply uncomfortable with admitting they were wrong about anything. Admitting you were fooled by climate denialism is a blow to the ego. Can't have that. Better stick to the current stance. And if it happens that the in-group also believes that, great, that's comforting.
We should probably come up with a way to make right wingers (the most scared people of all) think that addressing climate change plays into their in-group. Convince them solar is AMERICAN INGENUITY and that coal is a Chinese plot to poison the white race, and maybe you'd make some surprising (and awful) allies.
That or, like, completely destroy the Republican party, spend fifty years hard deploying green technology, and wait for conservatives to defend it because that's what they know, now.