Well, not everyone who's against JH-7 or J-10 believes the F-16 Block-72 will come. Pakistan's macroeconomic picture is as clear as day, there are scarcely few dollars available. Full stop.
It's a mathematical constraint, we can't import a nice new jet unless we have $1bn+ in hard dollars available every year for 10+ years.
When we had a better economy (via the 1970s), this was doable. When we had aid to hide the gap (Mushy), doable (but things went downhill fast post 2004).
The only now cutting the trade deficit, albeit with limited prospect of driving more exports to bring in foreign currency.
Our biggest mistake was not investing in developing critical tech like gas turbines or semiconductors at home (even if separately from defence). That could've given us a good base for exporting, attracting foreign investment, etc. To this day, we're still scoffing at it.