Yeah that's not a strong argument at all. The 2.4GHz and 5GHz bands are known widely as "garbage bands" due to how terrible they are to work with (e.g. rain will heavily attenuate your signal, they're literally how microwaves work to cook your food, etc.).

Moreover, there are plenty of radios on the market that transmit all kinds of noise on these channels that isn't WiFi (e.g. my neighbors had a baby monitor that I could tell when it was on by how shit my WiFi was at that moment, FPV drones somewhat frequently use this band with proprietary analog video transports, etc.) This is permitted because these channels are "unregulated" (or, more realistically, "regulated for unlicensed operation").

On top of that, the FCC's official statement on this very topic was that what they really care about is the amount of power being put into these channels, as some aftermarket router firmwares of varying repute would let you crank the output wattage above FCC regulations for these frequencies (<1W power to stay within unlicensed operation regulations for 2.4GHz), and apparently some in-market WiFi routers picked up those firmwares as a "supported" option (I think ASUS and Linksys were both named). Most of these routers have since patched themselves to stay regulation-safe.

So, go nuts, just stay below 30 dBm/1W from the transmitter in 2.4Ghz channels or prepare for a visit from the FCC. (You'll have to do your own research for 5GHz).