economic size is probably not a good judgement in this particular case because its not fair comparison, Turkey will get access to better/easier access tech than China, they just won't get the F-35 as a turnkey acquisition program.
True that Turkey so far has more access to Western Tech or potential partnership with Western source. However it's not always definite. Look of their Altay MBT, the moment German hold the engine transfer, the program face delay. Turkey now try to find another source, but I bet it will cost them more as Altay from beginning is already build for using MTU Engine.
This's what I mean with Turkish ambition for more Independent Defense Industry (which in turn), support their more Independent Foreign Policy vis a vis to NATO/West mainstream policies.
Like in my previous post where I compared Erdogan aim with what DeGaule 'independence' policies movement within NATO in the 50's and 60's..the problem with Turks compared to French even in that era was and still is the level of French Tech and Economics based then even relative compared to what Turkey have currently.
The French can get most of their need mostly from their own Industrial and Tech based, while despite all the progress of Turkish Defense Industry, many key components still can't be source internally and have to rellied on foreign partners.
And this is not problem for Turkey alone, but problem for many developing nations even most of developed Nations that want to have more capabilities for their local Defense Industry.
If you can't find some key components due your local tech based or Industrial capabilities, then you have to rellied on Foreign Partners to get it..thus it will cost more.
This is what I see the problem with Turkey ambitions. They want to develop most of their Defense need locally, in relative short time (even two decades is short time considering their ambition), which then raised question where the money coming from related to the size of Turkish economy (considering they have to rely to Foreign sources for some of it's key components).
Unless they can get backing from Rich Emirates in Gulf, which will be difficult since:
One, they are not in close term with some of those rich kingdoms like UAE and Saudi, they are closed mostly to Qatar,
Two, few of middle east rich kingdoms like UAE and Saudi have ambitions to developed their own Defense Industry them selves,
In short, where Turkey can get more money to develop their ambitions ? That's why I said they have to moderate their ambitions especially the time table. This in turn can reduce their own independent policies toward West (unless they risk more tech transfer hindering as they are begin to faced presently).
This is something that French even in the 60's have relative advantage compared to Turkey now when they move on having more independent policies toward/within NATO..French have relative more money and more Tech based.
However will Erdogan aware on this ? this is the big question. Erdogan big ambitions will cost big and even can be too big compared to Turkish economy size. Erdogan is not in possition like Iranian Mullah or Kim's family on spending much of their economy toward Defense ambitions. More and more opposition emerge stronger toward Him in Turkey. If he bankrupt Turkey on his Defense ambitions, this can be the end of him.