An employee working 10 hours a week is already a thing, it's called part-time work. Part time employees have fewer benefits and exist in many industries, e.g. food service. A weekend barista at Starbucks is not an independent contractor.
A weekend barista is only comparable to a gig economy driver the day that they can decide on a whim to show up to work for an hour or take a 2 week break unannounced, bail in the middle of a shift, or skip a shift altogether with no repercussions.
The barista doesn’t bring their own espresso machine, isn’t expected to eat all externalities and fund their own healthcare and pension. Granted I don’t know how that works for employees in the US either, but that has always been the point of contention in Europe.
The ability to choose their own hours is only one of many complimentary litmus tests that determine whether or not someone is an employee or a contractor. It is not a solely sufficient, nor a necessary condition of classifying someone as a contractor.
