There's a huge difference between warming over a couple tens of thousands of years (natural rate), and warming over a couple of decades (our current trajectory).

That difference is the eradication of much of life on earth that is unable to evolve to a new environment. For example, insect numbers worldwide are drastically lower than decades ago, and insects are required for almost all pollination of plants and a key source of food for small animals. The "food chain" collapses if there is no first chain.

Even a partial loss of ecodiversity can lead to further problems later.

Our efforts are certainly not in vain.