Say you have a minority that's 1% of the population, and unhindered it would also make up 1% of enrollments.
If you don't allow that minority to enroll, you're increasing the acceptance chance of a majority group member by just over 1%, while decreasing the acceptance chance of the minority member by 100%.
The correct way to describe this is then most definitely discrimination against the minority, and not affirmative action for the majority.
Actually Jews were about 1% of Soviet Union population and 5%-10% of University students. If Jews were only 1% of student population it would not be an issue. I went to mathematical magnet school (best math school in 5M+ city) and easily 30%-50% of students had Jewish roots.
Essentially it was more difficult for Jews to get into university, neutral for Russians, easier for Tatars and some other minorities and extremely easy for what's called Northern Minorities (they had - and still have special quotas, no exams necessary)
Speaking as 1/4 Russian-Jewish, 1/4 Chuvash, 1/8 Latvian and 1/rest Russian.
Say you have a minority that's 1% of the population, and unhindered it would also make up 1% of enrollments.
If you don't allow that minority to enroll, you're increasing the acceptance chance of a majority group member by just over 1%, while decreasing the acceptance chance of the minority member by 100%.
The correct way to describe this is then most definitely discrimination against the minority, and not affirmative action for the majority.