Wasn't the other big issue that motivated the FCC the devices which ignored / broke DFS [1], and the use of disallowed channels (eg, 12-14 in North America)
Interfering with licensed radar installations would seem to be a legitimate problem.
To its credit, OpenWRT/LEDE community implemented DFS per the requirements they were able to glean from regulatory bodies. Open firmware can indeed be hacked to operate against its authors' wishes, but as other comments indicate, closed firmware isn't inherently immune to the same exploitation. https://openwrt.org/docs/techref/dfs
Interfering with licensed radar installations would seem to be a legitimate problem.
[1] http://www.ieee802.org/18/Meeting_documents/2007_Nov/WFA-DFS...