This is actually probably the best thing OpenWRT have done in quite a while. I got two (one for a backup) and I've been super happy. I've happily used TP-Link, GL.iNet, and Raspberry Pi 4 devices, with OpenWRT in the past, but nothing beats the "it just works" aspect of a first party device designed for this, fully open, and a reasonable price.
Most off-the-shelf devices have too slow of CPU for a low latency/buffer router. The Raspberry Pi 4 is easily fast enough but needs to use USB3 network adapters which require packages not in the default rpi4 OpenWRT image. Not insurmountable, but a consistent pain every upgrade.
I ended up building my own image of OpenWRT to make the package hell better on upgrade, and as a bonus, I was able to build in my configs too. Recovering from a failed Pi was as simple as flashing the most-recently-built image. Upgrading just required rebuilding the image (and resolving whatever went wrong, of course, though it was usually pretty light). As a bonus, it's easy to swap SD cards on the Pi so I can have the last "known good" config available while taking the update.
Now I run OpenWRT on one of those x86 mini PC boxes with 4x 2.5GBe Intel NICs because my wirespeed is 2 Gbps symmetric, so I needed just a bit more oomph than the Pi could provide. The hardware is somehow even _less_ reliable than a Pi 4 - I'm already on my third machine in 3 years. I would love to find something more reliable.
OpenWRT has also made it incredibly easy to package in any arbitrary pkg into image downloads from their website. You don't need your own build infrastructure now.
I'm curious what your experience would be like with a Pi5/CM5 solution using PCIe for your ethernet. It is pretty easy to have spare boards and SD cards around for Pi setups. I've had good reliability with Pi setups using good passive cooling (no fan to die).
Not a huge fan of the design decisions on that one. $250 target makes it a hard sell to anyone but network nerds. At $100, I would have no issues making that the default recommendation for anyone, regardless of technical knowledge. Being a premium point requires justifications beyond open source warm and fuzzies.
Network enthusiasts are likely to already have separate switches and WiFi points. Let the router just route.
The CPU in such switches is far too slow to do any data plane operations, so performance is entirely due to the hardware switching. Replacing Ubiquiti's OS with OpenWRT just gets you a different management interface for configuring the hardware features that actually handle traffic. (Unless for some reason you desperately want to have a VPN endpoint that would be limited to a few Mb/s at best.)
Ubiquiti make great hardware, however a lot of people hate the software as it is buggy and inconsistent. This at least gives those people options to run something a bit more opoen and manageable under the hood.
