Such "stuff" happens everywhere in the world. It's way travel on seperate PNR's is always a risk something needs to be aware when planning this way. Last time I took the HSR in China to PEK, it arrived 1.5hrs delayed (and that was on their SHA-PEK line) - basically if a train gets delayed a bit, it becomes the victim rather fast and most make room for other trains so they stay on time. Better one train heavily delayed than each and every train creating a domino effect. Overall, obviously, HSR is quite reliable, but I'd not go with too tight connections including it when taking flights either.

As others said, try to make it a T3-T3 connection by taking CA. If there is a later flight (ideally by the same airline) STILL being perfectly fine to make the connection, it adds a bit more safety to it as well. Thus in thise case I'd go for the CA1232 flight. Leaves decent time for breakfast in XIY, heading to the airport not crazy early, and then a bit extra safety "just in case".