I think it really demonstrates how much more important execution is than an idea. Being the “simple” version of X or X for “niche user” can be a viable strategy rather than coming up with some revolutionary product idea. It also lends itself to competing as a small team, since larger competitors can't afford to pay close attention to those smaller verticals.
There must be a lesson here in doing one thing well.
Thousands of people choosing to pay when there is a massively more powerful and fully featured free alternative.
Web analytics have also been around for decades, and even today there is no shortage of competition.