Several receivers on and coming to market support MPEG4 4:2:2 in the chipsets, but not in MPEG2. Until the CBS transition to MPEG4 4:2:2, there were only occasional backhauls and feeds using this format. When CBS transitioned to MPEG4 it appears that they also implemented Irdeto encryption during prime time. I am currently viewing the CBS feeds and they are unencrypted during the daytime hours.
Not sure why you suspect a dupe... There have been many MPEG4 4:2:2 feeds for several years now and we have been viewing them with PCI and USB tuners. Seems fair and honest that the Zgemma distributor is providing potential buyers a warning that while the STB is capable of MPEG4 4:2:2, the CBS feeds are now encrypted in the evening.
If the Zgemma H7 supports MPEG4 4:2:2 by loading the latest OPLI release, then it is just an additional format that a STB can tune and raises the bar for other STB manufacturers and distributors.
The only reason I would not recommend the purchase the Zgemma is the lack of Blind Scan. If that function is enabled, it would be a very capable primary receiver for hobbyists.