The fact that temperatures go up and down does not mean that it is a random variation that just happens for no reason. There are always reasons. It is Physics. However, we do not have any detailed data from 100,000 years ago, so it is hard to find the exact reasons for the past.
But today we have increasingly detailed measurements (for the past 50-100-300 years) and we can find the reasons for what is happening. The current upward tendency is caused by humans, there is no question about it.
Of course, Earth will survive if temperature goes up 5 degrees, and it will survive if temperature goes down -10 degrees.
Humans will also survive. Humans live in Sahara, Eskimos live in the North Pole, humans can adapt. And you know what? The richer you are, the easier you will adapt. The rich will always have AC, heating, good insulation at homes, solar panels at their homes, and will always have money for food. Now the poor and the middle class... well... perhaps life will become harder. But do the rich care about the lower classes?