I'm a fan of IBL style courses. I don't know if it scales well but it isn't obvious to me that it can't. If a student can teach better than the teacher, then that should be good enough. The point of higher education is to create independent critical thinkers. IBL is particularly good at this in STEM courses by my personal experience. It's a narrow perspective admittedly.
I suspect this is how education was really done before all this non-sense about grades. Elite schools select for the the best teachers anyway. Plus, knowing that students can eventually produce other students makes it easier for researchers to focus on their specialty. They may even come to the students for help.
I'm not a big fan of time and deadlines either. Being quick and clever is great but you can do just fine being a conventional thinker that is persistent and diligent. The point is to refactor the academic system to be robust enough to adjust to a person's life. Right now it is a rigid system traumatizing the people it's supposed to serve.