Good points TypeRated.
Another dimension that needs considering is the Force Protection angle.
Any aircraft might win a Top Trumps battle against any other - but in addition to the operating costs and the 'purchase' price, it has to be kept safe on the ground when / if deployed.
Having your low tech bad man lobbing shells onto the airfield is a pain and chuffing dangerous.
The attack on the USMC harriers showed what could be achieved if taking inspiration from the SAS's North African adventures in WWII. If fighting a more high-end enemy how much more will need to go into defending / protecting the flight line or even the crew rooms & accomodation?
I am sure that the TacEval flashbacks may now start for some. Sorry.