You make a good point that one solution to this problem is getting the incoming Chinese students a better English education. They obviously don't really have it before arriving, and schools want their tuition.
Schools should enroll Chinese students in English education for 3-6 months prior to the beginning of the term.
Cool. A big thing about learning language is getting the confidence to speak. You can get that by practicing with some native speakers.
In the classroom, if students don't feel comfortable speaking, they won't ask questions. If they don't ask questions, they won't learn as well as they could by asking.
Schools should enroll Chinese students in English education for 3-6 months prior to the beginning of the term.