Most people who say that they believe in a climate crisis do not change anything about their behavior that shows they believe it. They heckle people who say climate change is nothing to panic about, and then get in their fuel-inefficient SUV and drive home.
This hypocrisy is quite common when people feel they must follow an established social norm but are unable or unwilling to follow it. In the case of climate change, there is very little that individuals or governments can do. We need our cars, we need our industry, and we need a healthy growing economy.
Hypocrites also doubt that climate change is so severe. After all, if carbon dioxide in the atmosphere has increased by 25% over the past 50 years, how will an increase of 5% over then next ten years make much of a difference? Common sense is your enemy when you must believe.
Failure to follow a moral rule that is enforced by a society, or by a social group, makes people even more eager to enforce it on others. Hypocrites witness others being heckled for lack of compliance with the rule. Knowing that they themselves don’t comply makes them nervous. The best way to avoid becoming the target of heckling is to enforce the rule on others.
That’s why people who are secretly racist express strong support for anti-racism, men who are sexist call themselves feminists, and people who doubt climate change act angry and defensive when anyone questions its existence or severity.
The same behavior can be seen among religious followers, as many church-goers have likely witnessed. The strongest doubters, and worst practitioners, are often the most eager to enforce moral rules on others.
This mechanism becomes a useful tool for social control. If you can establish a new moral social norm, you can get people to enforce it. The less practical it is to follow, the more likely people are to virtue signal and enforce it on others.
Moral hypocrites also demand that government solve the problem. Political parties and governments promise to do “something,” to appear that they are acting. This is satisfying to the hypocrite since appearance is all that matters to them.
If you point out that government programs aren't working, the hypocrite will ignore you or get angry. The government virtue signals on their behalf, and that is all they want.