That's a slight miscalculation the article makes -- ignores that by reducing spending in the consumer level, also corporate (e.g industrial) spending is reduced. But that's not the real gist of the article, and it doesn't reduce from the core message.

The thing is, this "invididual reducing" is never enough or workable in itself. That isolated individual decisions by themselves can lead to sustainable change is the real myth (and the lack of real impact of all this "shorter showers" and "recycling" campaigns reflect that).

Invididual action only matters for large scale effects when it gets systematic and organised and ends up as some general guideline (from a new law to a regime change). However we like heroes, for example, Rosa Parks didn't end seggregation. Millions of black and white civil rights activists, demonstrators, lobbyists, etc, did.