Disable 2.4/5 on Orbi RBR50

As you have learned, Netgear does not provide the option to turn off the WiFi radios on the Orbi product line.  We can only speculate what led to this decision, as other Netgear products do provide this option.  My own (personal) thinking is that managing devices which can connect to both bands and can roam from one Orbi device to another is so deeply ingrained in the product design that "things may break" if the WiFi capability were not present.  Anyway, "it is what it is."

And, yes, it appears to be possible to use telnet commands to disable individual Orbi WiFi radios.  It is not supported by Netgear, and my observation is that people find it a frustrating experience.  There are some LONG posts about "Separating 2.4G and 5G SSID" that have instructions buried in them.

What a fascinating concept: to install an Orbi system for the sole purpose of using the hidden 5G WiFi connection as an ethernet bridge.