The dynamic makes sense: the more popular the question, the more likely it is to get asked early on. That means early answerers will reap benefits from the popularity of the questions down the road.

There's definitely an "interest" dynamic to it, but there's also something like consuming the solutions with a good effort-to-reward ratio inside a search space early and then subsequent solutions get harder (kindof like a cryptocurrency?)

Niche questions do present an interesting opportunity, though. My highest-ranked answer was about rolling your own setInterval / setTimeout function for JavaScript implementations running on the JVM that didn't have them. Not a hot topic, but apparently a few dozen other people cared about this over the years.