It's economically naive to think that "people clinging to the past" is somehow the root cause of Brexit and Trump. Why do people cling to the past? It's usually because they feel uncertainty around something in the present and foreseeable future. And for many who cast their vote in favor of these dubious causes, the present was materially bad enough for them, whether through unemployment, stagnating wages, or pay cuts, to take the chance.
In our bubble where we work in tech with stable, high-paying jobs, health insurance, and benefits, these people look hopelessly provincial. But it was by ignoring or dismissing them in the first place that Brexit and Trump were allowed to happen.