It seems this discussion is many years old. Of course, metrics won't help you run the business better, if you don't know how to run the business. But if you do, you can't do it without metrics. Nothing can be executed, if you can't measure it. Read this blog post, it's relevant: https://www.yegor256.com/2018/10/09/can-you-control-us.html
More and more people every year turn into freelance mode of work. This is an inevitable trend, and I'm talking not only about Uber drivers. Programmers, writers, journalists, designers, many people who need a computer and a cup of coffee. Read this PDF from Zerocracy, they nailed it there: http://papers.zold.io/freelance-deck.pdf