So, I've been talking to a lot of Uber/Lyft drivers, and while I have no carefully tabulated data to quantify my point, I must say Lyft drivers complain less than Uber drivers (at least not explicitly) about their respective employers.

This attitudinal difference is most acute when the driver drives for both: they generally like Lyft better for how the company treats them but are also on Uber to ensure steadier business.