You're absolutely right. But this is the perennial question of what sort of site HN is supposed to be. If the criterion for frontpage threads were importance, then HN would be a current affairs site—a completely different mandate from the one we do have (https://news.ycombinator.com/newsguidelines.html).

Optimizing for curiosity [1], which includes whimsical things like "Doom on a dongle" or "how much do all of the ants in the world weigh", and so on, means less space for a lot of more important things. Far more important!

[editing - bear with me...]

[1] https://hn.algolia.com/?dateRange=all&page=0&prefix=true&sor...