Probably for command line tools that need to add some level of hierarchy into their output. You can add 1 to pad length and pass it to a subcomponent to display its output.

I don't have any use for it either, but this package is not important by itself. It happens that this package is (was) at the very bottom of the dependency chain for some huge packages (like Babel, Webpack, popular frameworks, ...).

When its creator removed it, they literally destroyed the foundation of those popular packages. That's what made it suddenly important.

The less there are dependencies, the better.

Yes, dates are very complicated. But that doesn't stop pretty much every modern language from having good built-in support for doing this, because it's such a totally common task. JavaScript is such a mess. It doesn't even support integers, for crying out loud, let alone decent date/time/timezone handling. That moment.js is the most popular band-aid to fix this, despite it having a nasty gotcha API that mixes mutable and immutable functions/types in confusing ways just rubs salt into the wound. Heck, you can't even compare two moment dates with inequality operators without either casting them by prepending a plus sign, or calling functions - it just silently does the wrong thing.