The first sentence does not connect to the second, and the second is simply false.

Also, the first is much too vague to pin down to anything precise: was switching from agriculture to factories a case of "our way of life going extinct" to those who lived through it? Was universal suffrage, universal education, and the introduction of state pensions? Was broadband?

Almost everyone who loses culture to climate change, is going to be those who already lost a lot of it to the European powers from around 1870 to 1914 (not that this makes it alright, especially as the actual harms that population will get in the absolute worst case scenario where such cultural loss occurs is the much worse fate of "being shot at by border guards when trying to migrate").

The only science that will be lost, will be in the form of secrets learned by governments that fall and which others didn't discover independently.

We still should try to stop, even slightly reverse, climate change; just not because of the arguments you're making.