drinkingbird
Part of the Furniture
You are right, but such devices are rare, and even in the early days of WiFi 6 there are still many devices that do not support 160mhz.
Since the downgrade, the AX86U has been working at 160mhz, which proves that the problem is firmware related. @RMerlin
More likely driver related which he has no control over, if Asus updates it, it makes it into Merlin firmware too.