It is all related, so everything taken together does indeed matter. When we as consumers insist more on buying locally produced, durable, interchangeable, replaceable, repairable (!) components to build things we're actually likely to use for a long time, we can stem the flow of cargo ships and ditto planes shipping "stupid disposable junk" halfway across the world, thereby limiting all the pollution and waste of (fossil fueled) energy that goes with it.

While we're at it, we should demand to put an end to the senseless hoarding of patents and IP, in particular those that hamper interoperability between components, and for information on interfaces to be made public, so no more proprietary connectors, protocols, APIs, no more artificial restrictions on consumables such as printer ink, etcetera.