I am sorry but I am still very confused as to what efforts the CAC has made to market the J-10. I am not advocating one way or another about the quality of the J-10. It is possible that the J-10 is so advanced that the Chinese don't want anyone else to have it. It is also possible that the quality of the J-10 is so poor that China doesn't want anyone else to know about the severe weaknesses of the fighter. No matter which one, or somewhere in between, the quality of the J-10 is not an issue here.
I am not in any way questioning / guessing a potential rationale for why they want to / don't want to sell the fighter. What I question is the actual evidence that China has been marketing the J-10. It seems to me that most of the supposed evidence comes from potential buyers wanting to buy / interested in considering the J-10, but not CAC/China wanting to sell it. Sending the J-10 to air shows is not evidence of marketing the plane. They've sent the J-20 to air shows. I don't think anyone would ever consider that as evidence that the Chinese want to sell their J-20... I can clearly see that China and Pakistan want to sell the JF-17. We've seen solid evidence that they are actively marketing the JF-17. I myself have not seen any similar effort on the J-10.
They have not marketed it themselves, but there have been persistent rumors of supposed sales.
Most likely it is a combination of both factors. The J10 is very advanced, but not advanced enough to always merit the costs potential buyers must pay.
Bear in mind that the domestic flyaway cost is heavily lowered due to state ownership. Foreign buyers don’t have that advantage.
It is rumored that Bangaledesh is in negotiation to buy a squad (12-18) of J10CE.
This is supposed to cost 1 billion $ in loans + undisclosed sum up front.
We are looking about 75-100 million $+ per piece. That can almost buy you a F-35 if you are on good terms with America.
Most countries looking to buy right now either want fast ticket into stealth or something to lob bombs at insurgents. The J-10 ain’t the former and is way too expensive for the latter.
Bangladesh is a special case since they don’t really have a chance to get 5th gen but needs something to take on India’s droves of 4th gen. That’s the situation J-10 was built to handle.