For Netflix Originals, I would assume most productions are done on rental gear. The difference between renting an FX3 and an FX6 isn't going to be significant at production-budget scales. (And if you had a real burning reason to use something off-list I would bet they can write you an exception.)

The quality of global shutter cameras is simply nowhere near the quality of rolling shutter cameras, though there are more acceptable options showing up these days, they still typically have lower dynamic range and generally worse specs.