@EmptyNestSoon2 shows how things have changed in just one generation. Sad (truly) but true. I’m sure it’s possible to land a great job without that internship but, especially for strategy consulting gigs, you better be doing something really interesting (to them) if not interning. Of course, always outliers.
The issue is the process. They have built a path for UG , and then again for post MBA, and align most of their resources to recruiting to those classes. Training is set up that way. If you don’t come in those doors, you better network like heck, know a Partner, and have a really interesting story to tell.