I have a theory, and I have no evidence to back this theory up. The increases in anxiety in the general public over the last decade or so is in large part to people knowing we're on an unsustainable path. We're all collectively marching towards the edge of the cliff to jump off together. More people than ever have anxiety because we subconsciously (or consciously) know this. We're unsustainable with how we pollute an…
And of course, then there's the constant media hysteria driven by an obsession with social media stats and clicks too. Things are bad in many ways, but if you went by how the press spins it, you'd think the apocalypse was about to hit next week.
That'd surely increase a lot of people's anxiety, even more so if their sources are particularly slanted in a certain political direction.