Some colleges got around this rule by offering new international students -one- in-person class. Some schools, like Harvard decided to stay online only...

Newly enrolled international students whose colleges and universities are operating entirely online this fall won't be allowed to enter the U.S. after all.

https://www.npr.org/sections/coronavirus-live-updates/2020/07/24/895223219/ice-confirms-new-foreign-students-cant-take-online-only-course-loads-in-the-u-s