This device specs vs price aren’t appropriate in any way. There’s no point paying 100€ for something that only has 2 Ethernet ports, doesn’t have modern WiFi and only 1GB of RAM and an older CPU.
Besides the whole title and movement is a but misleading because the guys from Banana Pi shipped multiple boards already that are built for OpenWrt and have things like WiFi 6 in that price point. One of them is the “Banana Pi BPI-Wifi6 Router” for 60€ and more expensive the Banana Pi R3 that that just makes a lot more sense.
Check this out, the router from the link for someone in Europe:
Now the other ones:
I guess you get the point, all Openwrt routers and the last one is much much better in all ways.