>>520541039
Plenty of planes throughout history that had excellent potential which was never realized because they could not be sold to anyone for whatever reason. The F-20, for example, could have been a reasonable F-16 alternative, but the US government forbade its export. The Su-75, in the unlikely event it does fly someday, will have to face the already established Su-57 domestically, and the J-35 abroad, which means its chances aren't great.