I like that this series of articles is taking into account the "Total System" cost of utilizing UAVs. I wish they in turn would do the same for manned aircraft instead of only counting development and "fly away" costs. There are huge investments on the ground for ANY air vehicle. It would be better at providing apples-to-apples comparison.
However, I have to question some of the article's assumptions.
One, there doesn't seem to be any calculation for "spares" or units undergoing a programed maintenance. They simply count up how many 4-ship "CAPs" there are "claimed" by the USAF. For manned aircraft, the USAF plans for x numbers of loss replacement and aircraft in "overhaul" outside of the number of aircraft available operationally. These unmanned vehicles will require ... assuming some survive
... periodic upgrades of hardware/electronics/software. Also, does their aircraft purchase count minus operational "CAP" count include aircraft operated by "others" outside of the USAF?
Another thing not factored in here is that the main attraction of "drones/UAVs/UCAVs/Whatever label is used today" is that they do not carry a pilot and are considered expendable. In that sense the air vehicle will not have the same redundant and reliable equipment that a manned aircraft will. I would expect and the DoD (and other users) would expect a heavy attrition rate. The REAPER moved the "cheap/light-weight" PREDATOR from a simple throwaway recon air vehicle to a fairly heavily armed light attack air vehicle. The article authors should try to figure out how many "manned aircraft" sorties would have been required to to do the same number of missions the PREDATOR/REAPERs have done since 1998.
Other UAV types are designed for greater survivability than these low-end, "low intensity" conflict UAVs.
Communication/control of an air vehicle beyond sight is always tricky. The DASH drone helos from the 1960s suffered heavy losses due to operators losing control. There is more than one way to have communication/control of a "drone" and some or all links "Should" be secure. If there are issues, they need to be addressed. Don't think that some of these same issues already wouldn't also impact "manned" aircraft as well.
Personally, I think that a mix of manned and unmanned aircraft are required by our Armed Forces for our defense. We are not at the point where "launch-and-forget" drones will be fighting wars without a human in the loop. Makes for a nice SF movie ... but not for real. I kind of doubt we will for a longtime.