The technicality isn't radio waves. It's object size. FCC rejected Swarms application because it wanted to use satellites smaller than the smallest 1U CubeSat specs. Apparently, tracking for these objects gets much hard the smaller they get, or something like that. But once its up, it's up, and the physical risk cannot be mitigated with an off-switch the way signal interference could, there are simply now 4 quarter-U sized sats too small to track as effectively as standard sats, which risk analysis had shown posed a too-high potential for harm.