I have many nerdy friends who have been Linux users for ages. But most of them don't know such a thing as Openwrt exists or have never bothered to give it a try.
It's a very fun piece of software to play with and can be extremely useful for routing traffic.
Wondering why it isn't more popular/widely used.
I use OpenWRT on my Linksys WRT3200ACM because I used to have a cable connection that suffered from bufferbloat. The SQM feature made a huge improvement. I eventually switched to a fiber connection from a different ISP which does not suffer from bufferbloat, but I kept OpenWRT on my router.