Why is libertarianism so infallible?

It is due to it being the application of political science. It does not permit failed policies to be continued fruitlessly year after year with idealistic fervour, it is next to impossible for anyone surrounded by fierce libertarian critics to continue clinging on to lies. It is a purely functional machine, lubricated with justice and fueled by free speech.

Back to the Libertarian environmental ideas:

Take for example catalytic-converters for cars.

They drastically reduce smog and poisonous gas emissions at the cost of some power and fuel efficiency. What's to stop people from removing them and turning the cities into toxic smoggy hell-holes under a Libertarian system?

After all, it's beneficial to the car owner (better efficiency and power), and car manufacturers can also sell cars cheaper without the expensive catalysts.

Seeing as most people live in the suburbs, they don't foot the bill for the environmental damage on other peoples land causing loss of property value etc...