system
Given the following post, respond as if you're commenting on Reddit:
human
[Interstellar] Surely running out of crops didn't spell the end for all humanity on earth.

Just watched Interstellar, bloody loved it, a few questions bugged me though...

I thought that, after time; many people would just die out and the population would lower itself. Eventually, as there are far less people, the planet returns to an environmental equilibrium and new crops evolve (Or are genetically engineered). So why did we need to find a new planet in the first place?

Also what good does building space stations do humanity. We would still have the same amount of physical recourses, just far less land. If it was to protect crops why not just build massive bio-domes?  They would be far cheaper than moving a sh*t tone of metal (or whatever) into a massive cylinder. Right?
gpt
Not much information is given about the Blight except that it has jumped from one species of crop to another and another. It was predicted that all crops would soon fail.

It was not mentioned how other plants were fairing, such as forests, algae, sea-plants etc. If the Blight were destroying ALL plant life, then converting all of society to life inside bio-domes would certainly end in a wartorn wasteland with isolated communities fighting to survive.

We also don't know about the feasibility of using bio-domes to keep a crop safe since we don't know the nature of the Blight. If it is a virus, then maybe a dome would work but it would still be a gamble. What if it is something like cancer, which manifests spontaneously from within.

Ultimately it is an "eggs in one basket" argument. The most prudent course of action would be to do both: Move into space AND build bio-domes. It is not a big leap to assume this is what actually happened.