Video: "Forget Shorter Showers," 11 min from 2015
I try to divide my time equally between lifestyle choices and causes that address the big stuff: large agriculture, the petroleum industry, nuclear power, over development, mass transit, etc. etc., etc.
I think both approaches are intertwined. If more people grow their own food and/or commit to buying locally (or dumpster dive), that's less money for the large-scale polluters. And when individuals do it, hopefully they're leading by example and encouraging others to do the same.
Meanwhile, I think it's important to to do all we can to support movements like #DefundDAPL (and I did close an account because of this).
The world's such a mess now, I don't think any approaches should be ruled out or dismissed in favor of others.