The issue is that downloading a software, for most people, implies an investment in the task the software does that is unlikely to be paid off if it only does a single simple task. If I'm going out of my way to download something, then I'm probably willing to learn a few knobs that give me more control. Hence why I suggested that such a person would rather use a website.

This is really just my read for why this sort of software isn't more common. Go ahead and make it, and if it ends up being popular I'll look the fool.