The good classes all have <30 class size. If you take Honors classes you won’t see many people. Typically the honors econ track (ECON 20010) starts with two sections, 80 people total, but by the end of the sequence there will only be 20~30 people left. It’s the easy classes that are filled with people. Most of the time you can easily swap out a requirement for a better class with better professors and smaller class sizes (so less crowding during office hours) and challenge yourself more.
Some really good classes with Nobel faculty/highly esteemed professors can sometimes only have a dozen people enrolled. So honestly it’s just an issue of people not seizing a good opportunity.