Plenty of employees have no upward mobility either. Though with 10 years of positive ratings, I would think The Algorithm would reward them with more frequent/better gigs?

I'm an employee. I have 9 years experience and a masters. I had one promotion. I've been stuck at the intermediate developer level and do not see any promotions in my future

The Algorithm could decide their car is older and they could get less gigs :-/.

She has upward mobility. They let her choose the rate she charges the customer and then they take their cut. The more hours she wants, she can have. If she's good at her job and the customers love her, she can give herself a raise by increasing prices (it's already like $50-120/hr depending on the class). She even has the authority to hire someone to work under her.

That depends on the type of gig. There are some gigs where experience and skill command a substantial premium.

The largest gig employers (Uber, Lyft, Doordash, etc.) do not seem to provide a substantial premium for experience.

In 5-10 years, what will be the current driver's expectations for pay?

Beyond a month or two of experience, what would more experience benefit in that role?