Mudiay played like 10 Chinese League games and didn't do that great.
In his 12 games he averaged 18 points and 6.3 rebounds and 5 assists on 48% shooting, those are not bad numbers for an 18 year old playing in an adult league. The kid missed three months with an Injury and then stepped up in the playoffs scoring 24 points to help his team advance. He did struggle the next game being pressured and asked to do a lot. I am not sure what you expected him to do in a league filled with Men he was playing against and plenty of former NBA players.
He might not win Rookie of the Year but his stats and playing in the Chinese league have nothing to do with that. Its also okay not to like him. I think he is going to be good.