Uber seem to fail most of these "in business" points for their drivers with their heavily one sided agreement.
Going back to IT contractors and IR35 in the early '00s it's been a constant "discussion" of where the line is. For contractors we had to get quite good at amending contracts, and satisfy other aspects to be able to remain unaffected. In that case the govt wanted us to be employees, contractors didn't!
There is only 2 drivers who led this case, and they currently work for some private taxi cab association.
For drivers I don't understand the appeal of being self employed there's nothing to gain by it.
If they still want to show they're operating as self employed they can with a b2b relationship with Uber, website and advertising, exercising right of substitution, and all the other HMRC indicators of being in business.
I don't know how many are in the '& others' in this case.
In many of these cases (especially those of the new courier firms who 'self-'employ drivers/deliverers) it looks and smells like an employment relationship. The courts are entitled to find that that's what it is.
For example, if it requires designers to only work through them, be available 9-5 every weekday with x holidays to be asked for weeks ahead, and accept a fixed hourly rate, I'm fairly sure the U.K. would judge the designer to be employed by the site.
Alternatively, if the site only is a broker who brings designers into contact with clients (free or for a fee), and a designer works for a single client for years, chances are (IMHO, IANAL) the U.K. would judge the designer to be employed by the client.