I didn't write about this possibility in the article, but there's also a universe of apps/tools/companies which do seemingly trivial things that don't transform anything on the face value and eventually end up being rather impactful. Take Twitter: for the first X years, many people dismissed it as that stupid thing where you write about what you had for breakfast.
Now it's basically a media company. Granted, no lives saved, but a major player in the landscape.
Point being: you can end up doing something truly revolutionary in the end by doing something trivial and useful at first. A better way to order pizza could become a better way to do [something that doesn't sound as banal].
(I would also posit that this kind of serendipity doesn't necessarily make you a visionary.)