No, Iranians don't think they're European. But there's quite a lot of dislike of Arabs because of their invasion in 1980. Understandable. Many people on this forum keep making the same mistake over and over again. People you'll find on English language forums are most likely emigrants. Comparable to the people who fled the mainland to go to Taiwan because they didn't want to live under the new government.
In any case, China in 2015 was not the same as China in 2025. The facts are simple. After the deal, Iran invited all countries, western and Chinese, to invest. China did invest but then pulled out because of trump.
They also started building an HSR line in 2015. But for some reason progress stopped. But it might now be picking up again as China has accepted being in a new cold war.
They also invited Huawei to upgrade their telecoms infrastructure. The west abducted the founders daughter and private Chinese companies have been afraid of coming to Iran since.
It's a clear picture. The Iranian government wanted China involved. Americans with Iranian ancestry and royalists with no support in their former home might think differently