Technical competence isn't as well evaluated at companies like Uber/Lyft/Airbnb at L6+ especially for external hires. So it's not so much that the technical bar is dropped but that it just is less enforced at higher levels. As a result you end up with a lot of ICs that are all talk but little else. This is, of course, a gross generalization. I've worked with and know great engineers of all levels at these companies. But Uber in particular had plenty of really bad apples that got hired into other companies across the bay at L6/L7/L8.