This is interesting. HomeKit insider has a first person report from CES saying that they were told that the Homekit router certification program has been discontinued, meaning no new models will be accepted for certification.
This does not mean that the existing models will stop working or stop working with HomeKit.
But it looks like the assumption going forward is that new router models will probably be matter certified instead if that’s a feature the manufacturer wants to provide. We’ll see.
Finally, we were told on the ground at CES that Apple has opted to discontinue its HomeKit router program and is no longer accepting new models for certification. This may explain why there have been no new and faster routers since the first Wi-Fi 6 ones shipped.
Linksys and eero both have Homekit certified routers, but I don’t know that anyone ever bought a router because of that feature. Judging from Internet comments, most people didn’t know what the feature meant anyway.