professor Duke has higher admission standards than most schools, for sure. It hurt them in the portal because they will only accept certain credits from other universities. That's why they mostly went after grad students in the portal.
Their backers have been begging the school to relax the standards in terms of allowing credits from other schools so that they can remain competitive in the new landscape of college athletics, but they are refusing to budge so far.
In other words, you can be skeptical all you want, but as of now Duke is definitely maintaining a higher academic standard than any other school in the top 25.