Xi got into Tsinghua not due to intellectual ability, but due to his political connections with the CCP. This isn't the meritocratic or technocratic story one might have assumed to be the case reading the above comment. China is ultimately a poor country on a per-capita basis and essentially a failure when compared to countries with a similar culture and historical circumstance like Taiwan. It's only their massive size that leads people to the faulty conclusion that they have anything worth emulating.
I'm fully willing to accept that he got into Tsinghua from connections, and at the time I'm sure there was mass instability and on top of it I'm sure he would have been able to avoid coursework if he wanted to, leading to the real possibility of low quality education. That's still far away from being almost illiterate.
