What this expression refers to is a pervasive false equivalence: the idea that anything that isn't perfect isn't worth bothering with, or that doing something small somehow hampers a greater task (even if when it actually contributes to that greater task). It is a statement against apathy and binary thinking.
This comes up in politics and activism all the fucking time. Like "Why should I care about car emissions when freight ships produce more emissions than all the cars in the world?" The answer is simple: because you can. Do what you can, even if it's small. That doesn't mean forgetting about the big polluters.
some sort of labor movement, a geopolitical shock, a massive strike, etc
If anybody is avoiding Amazon as an alternative to those things, then I agree that they need a kick in the pants. But I doubt there's anyone out there thinking to themselves "I don't need to take part in the revolution because I bought my cat food at CVS instead of Amazon".
This is really cool! I like the idea of pen and paper as a supported UI. I've never found handwriting on a touchscreen to be an effective or enjoyable experience, across the myriad devices I've tried it on (including an iPad with an Apple Pencil). And app-based form entry is often a drag. By the time I've even opened the app and clicked the "new entry" button, I often could've been done already with a simple pen and paper.