When the FCC says you must accept interference, that means you have to live with it if the interfering device meets emissions standards. It doesn't mean the device has to be functional in the face of interference.
Let me try an example: I have an amateur radio rig that transmits only on the allowed frequencies and it meets FCC standards. You are my neighbor using an antenna to get your TV. You allege that my radio transmissions interfere with your TV viewing. Legally, I'm allowed to tell you to pound sand and you have no recourse. Because your TV has to accept radio interference that is otherwise legal, whether your reception is affected or not.
(Of course, because I'm not a complete dick, I would assist my neighbor in properly shielding his TV or otherwise mitigating the situation, rather than tell her to pound sand.
It doesn't even mean it won't be irrecoverably damaged, it just means the manufacturer of the damaged hardware can't sue the manufacturer of the interfering hardware.
They must accept the interference in a philosophical manner more than a technical one.