I feel that is a weak argument and have never seen anyone prove that is the case. You can do that now with component cables. The majority of DVRs and tuner devices have component inputs. The fact is the cost of a ATSC modulator is prohibitive.Program providers do not want any boxes out there that can produce a QAM or ATSC signal output because the digital quality creates near perfect copies of their product that could be recorded by off the shelf DVR or computer with ATSC tuner.
You will not see receivers with such capabilities, perhaps some kind of sling type output that is more difficult to copy or HDMI over CAT5 type thing for distant displays.
I feel that is a weak argument and have never seen anyone prove that is the case. You can do that now with component cables. The majority of DVRs and tuner devices have component inputs. The fact is the cost of a ATSC modulator is prohibitive.