Hi,
I've got an RT-BE88U router with the latest official firmware, and I think Wi-Fi 6/6E is somehow disabled.
My laptop has a WiFi 6 adapter but it always connects in WiFi 5 mode.
In the WiFi Professional tab, the OFDMA/802.11ax MU-MIMO is greyed out with this message:
*Need to enable 802.11ax...