Earlier quoted context omitted.
My problem with that statement is that it describes every single job you could possibly have, even the very well paying ones. You are always trading your labor to somebody with money, whether it's an Uber driver or the CEO of a major corporation. It's not the "Uber model", it's the money represents an agreed upon denomination to trade goods and services with model.
The important part of wpietri's critique is "during the instants we are directly useful". The CEO doesn't stop being paid when she walks to the bathroom, and a cashier doesn't stop being paid when he's waiting for a customer to show up. wpietri is talking about a shift in the granularity of trading your labor for money, so that you aren't paid for a day or an hour of work, but for the exact number of minutes you perf…
As somebody who was a self-employed consultant for years, I get that being one's own boss has upsides. But I always maintained a large buffer of cash and could price in all the time I spent looking for work. Things like Uber and the new retail scheduling trend don't allow for that, and as far as I'm concerned amount to calculated exploitation of desperate people.
In some sense, that's nothing new in labor history; we've always had exploitation of desperate people. But that's no excuse for increasing it, and in particular I despise Uber's "we're just helping people be independent entrepreneurs" spin to cover up that exploitation, especially when their whole plan is to kick those supposed entrepreneurs out into the snow the moment they have self-driving cars.