[topspin]

There is nothing grey about it. Read it here: https://www.fcc.gov/general/jammer-enforcement

  Federal law prohibits the operation, marketing, or sale of any type
  of jamming equipment, including devices that interfere with cellular
  and Personal Communication Services (PCS), police radar, Global
  Positioning Systems (GPS), and wireless networking services (Wi-Fi).

If you use the device in this story to jam Wi-Fi you're a felon and the FCC will seize your equipment, bury you in fines and/or put you in prison. The "accepting interference" requirement does not immunize anyone from prosecution for jamming. Unlicensed != unregulated, and the FCC is perfectly capable of distinguishing between legitimate Part 15 operation and jamming.

[walrus01]

What the hotel used was not a RF-shitting noise source/jammer of any sort, it was other properly certified/permitted Part 15 legal 802.11 wifi equipment equipped with "rogue access point containment" software features that perform deauth attacks in the 802.11 air protocol. Example:

https://www.google.com/search?client=ubuntu&channel=fs&q=cis...

[Chris2048]

It is grey. It is illegal to jam, this is not jamming.