Amazing suggestion. I watched it a while back. I won't make the claim that I remember everything or even understood 100% of what was going on, but they really make an effort to untangle the complexities of our broken system and show how fragile it really is.
It's important to note that Michael Burry, the person played by Christian Bale, is buying up cheap land that owns the rights to water. Like many others he believes that a water shortage will turn into a huge crisis in the future.
Thank you, I didn't spot that inference from the film, but now that you mention it, it makes sense. I would ask our government to buy back the water companies they've sold off, but as we couldn't trust them to run a bath on current performance, it's hard to see how they would manage.