FRITZ!Box 5590 Fiber

If you can wire APs with network cable, that's always the best option. Obviously buy the same type, Ideally with central management, like Unifi for example. But for many, running the cable is just too tricky. In a network engineer, but live in an old brick-built house with hardwood floors and plastered walls. So I do use a mesh system in my own house. My ISP provided a FritzBox AX router, so I bought matching FritzBox mesh repeaters. This means I can make the router Master, and the repeaters all slaves, so I can manage and monitor everything through the router management page. The mesh repeaters have an Ethernet socket, so in some locations (like my home office) I've got a network switch and some hard-wired networking. Most importantly, to my PC. Gives me a Gigabit connection to my router.

GenieACS works fine with fritzboxes. What exactly does not work for you? How do you feed the ACS URL to your boxes, do they even register in the ACS?

i had horrible experience with the axe5400. went to fritzbox, never looking back

Used quite a bit by regional ISPs in Ireland

AMV Fritz.box. all you need to connect your stuff. Most is WiFi anyways, these days.