HORRIBLE wifi speed but ULTRAFAST via ethernet ports

I do not like the "Blocked" business with Satellite #1.  Thanks for taking the time to install WiFi Info View. Not being able to come up with any reason for WiFi device performance to be so low, I was grasping for anything.  Such as, "maybe the 5G channel is SO SATURATED that nothing can get any air time." The results do not appear to support that hypothesis.

5G WiFi is a bit confusing. (WiFi in general is damn complicated in my opinion.)  The router attempts to use an 80MHz wide channel (to get 866Mbps maximum throughput with QAM256 encoding) by combining channels 36, 40, 44, and 48.  When the customer "sets" a WiFi channel, that means the router uses that channel for management frames, such as Beacon Frames and set up communications.But, it still tries to use the maximum possible bandwidth based on the capability of individual devices.

It's hard to even imagine what is going on.  "Oh, you're a device that can do 802.11ac with 2x2 MIMO, set your radio to xxx and transmit to me."  "Oh, poor camera, you can do only 802.11n and no MIMO, I'll talk to you at yyyy."  Every transmission.

(A similar thing happens with 2.4G WiFi. If the network actually has an 802.11b device on it, communication with that specific device has a maximum Link Rate of 11Mbps (https://en.wikipedia.org/wiki/IEEE_802.11b-1999 ).  When an 802.11g device comes on, the maximum link rate is 54Mbps (https://en.wikipedia.org/wiki/IEEE_802.11g-2003 .  Only 802.11n devices are capable of reaching that mythical 400Mbps proudly touted in the RBR50 product data sheet. 

Even if we add up the "utilization" of channels 36+40+44+48 in that report, it comes to 30.9%.  (Not forgetting that we have no idea what the hell that report is actually measuring.)

Having failed miserably to find a solution, I can think of only one more step: the dreaded Factory Reset.  My practice is to first try a "quick reset":

• Save the configuration to a computer (web interface, Advanced Tab, Administration, Backup Settings.)
• Get out the paperclip and hold it in the tiny "reset" hole until the power LED begins to blink amber. (about 10-15 seconds).
• Let the router restart. (the web interface goes back to "admin" and "password")
• Go through the setup process and do not change anything. Leave the WiFi SSID/password the way it is. Do not "register" the product again.  Do not sign up for anything (Armor, Parental Controls, etc.)
• Just power through until you get to the page that offers two choices:
  • Load a saved configuration, or
  • Continue to configure manually.
• Load the saved configuration. The router will reset all by itself. And, everything comes back. (SSID/password. Admin login credentials. IP's assigned to devices.  DNS servers. etc. etc.)
• One time for me, whatever junk had accumulated and caused my router to act up was now gone.

Takes 10-15 minutes maximum. No data entry (no chance for typos).  No WiFi devices get the wrong IP addresses assigned to them.  Wham. Bam. Thank you (oops)