Ease of managing multiple OpenWRT devices is still its weakest link. OpenWRT is device centric, but I don't want to managed devices, I want to manage a network.

Modern mesh WiFi systems I've seen do that so well. I know in theory that I could create a VLAN + SSID on my OpenWRT router and APs just for iot devices to only access the internet. But setting that up on a TP-Link mesh was a couple of taps in their app. Doing it on my OpenWRT devices would be quite a bit more hassle.