His terminology is a little less than clear, but what he's saying is that most colleges and universities require 4 years of English in high school for students speaking English natively, but where a person arrives from a non-English-speaking background, the colleges also may require a year of ESL English. College-level courses require fluency in English since many courses are lecture-based with complex reading requirements, and the reasoning is that adequate cultural immersion in the English language probably did not occur for someone arriving without an English-speaking background, so the ESL class is intended to make up for that.
Obviously, different students may exhibit different proficiency in English and that may or may not be taken into account by the schools in specific cases. But colleges and universities are also bureaucratic structures, and sometimes policies are whatever they are, take it or leave it.