1) The whole point of Interstellar is, yeah, if you're facing an existential threat, more farmers isn't going to help you much.
2) Farming is one of the biggest contributors to climate change and perhaps THE largest contributor to humanity's impact on the environment.
We probably need to eliminate most farming and replace it with a synthesized vegan diet (i.e. grown in vats, processed to reintroduce texture, etc) if we really care about protecting the environment.
And it competes with nature for land and resources, especially water. And the need to keep pests at bay also causes big impacts. As does the run-off.
you must be joking. A lettuce which has grown in some backyards, with time and sun (and a lot of fight against various insects, true) tastes so much better.
But maybe your hydroponics are better than mine.
I'm all for optimizing farming if it's possible but I don't want any compromise on quality (taste, nutrients, whatever).
For a start we could just avoid wasting so much :