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.
Make that two, Turris also sells them, though technically it's a fork of OpenWrt with some stuff on top. I have one myself (though I'm not running the original OS).
The BananaPi BPi R3 and here is a very good option with a 4 core CPU, 2GB of RAM Wifi6 and two 2.5G SFP ports besides the 4 ethernet ports. There’s also an upcoming board the BPI-R4 with optional Wifi 7 and 10G SPF.