I guess I'm different. I typically want my router/firewall/network services box to Just Work. I've made a career in deep-in-the-weeds system administration and engineering. Having to hunt down man pages, examples, tutorials, etc for the dozen or so fiddly bits make up a modern Linux- (or BSD-) based router was fun the first time, not so much the 10th. Been there, done that, got the t-shirt.

I will concede that the OpnSense UI is far from perfect. I would really like to see a device-centric view that lets me set all the things related to that device from one screen (or possibly one screen with multiple tabs). For example, if I add a Roku device to my network, I want to enter in the MAC address and then be taken to a screen where it will let me set the hostname, pick a static IP address, hand it a specific DNS resolver IP, see all of the traffic going to/from the device, only allow it access to the Internet between during certain hours, etc. All of this currently requires jumping around between multiple disconnected parts of the OpnSense UI.

I feel almost exactly the same as you on the subject. When I was young and starry eyed I built my own router out of a PC running openBSD, all by hand. Nice learning experience, interesting OS, but definitely not maintenance free especially around system updates as back then openBSD packages and sys upgrades required recompiling everything. Now I do the same mini-PC thing as the OP's article but I just put OpnSense on it. Agree the UI can be maddening at times but the thing is rock solid, and has very polished update and upgrade mechanisms. Built-ins/plugins are great - unbound, wireguard, openvpn suricata, backups to git etc. Also I like that it is BSD based, my network experience was learned on Cisco's and Junipers in an ISP setting and Linux networking has always driven me crazy