Section 15.3.5 is for the power five conferences, which does have different rules. You'll notice in Section 15.3.4, which applies to the non-power five conferences, there is nothing prohibiting the non-renewal of scholarships for athletic reasons after the period of the award, which is one year in this case. I'm going to make a guess that most of the kids that do not find another home fall into this category.
Even with Section 15.3.5, nothing is stopping a coach from cutting a player from the team and forcing a kids hand. Stay at the school under scholarship but just be a student, or seek a transfer to place they can still do both.
https://collegebasketball.nbcsports....art-of-sports/
Like I mentioned earlier, plenty of ways for a coach to "open-up" a scholarship spot if they want to.