[spicybright]

Why would you use ascii for something like a waveform, something that's inherently a graph?

Sure, maybe you don't need that much resolution for what the use case is. But it's the equivalent of looking at a graph and squinting your eyes to blur it.

[jwosty]

In short, because text is much easier to deal with than bitmaps, and there is much more tooling that "just works" for text than actual graphics, like Expecto's textual diffing in assertations. @MayeulC said it well: https://news.ycombinator.com/item?id=28856884