Maybe. But remember that the plague in Europe killed about 1/3 of the population, and "civilization" continued onwards. (Maybe even improved as the feudal system collapsed.) And much of what we risk losing is the ultra-comfortable personal lifestyle advantages of 20th century technology.

What is likely is that the global population will be severely pruned at the low end of the socio-economic scale. And there may be massive political or economic change as a result, but basically the overall situation will look like it did under the traditional population pressures caused by disease, starvation, and war.

For example, if westerners became vegetarians, even a severely compromised food supply system could support the current population. That would require people to become vegetarians, though, and they don't want to. So they would probably have a war to resolve the question of who gets meat and who eats potatos and onions and cabbage. But that's just traditional old-style human interaction, and as you suggest, we evolved in that sort of environment.

Might be a bit uncomfortable, but not more than in the 1600s, say...