[rperez333]

Because it creates more problems than it solves. A movie set is expensive and moves fast – and keying is not as big of a problem as they made it out to be.

For example, Niko doesn't seem to be aware of the IBK keyer (based on his comments in the VFX subreddit), which is the keyer used on almost every shot in high-budget movies. While it's not a single-click solution, it's the main tool to tackle thousands of shots with defocused edges, motion blur, and semitransparency every year.

Niko deserves credit for bringing Paul's incredible experiment, but Corridor is at its core a group of entertainers, and most of them have never had experience in a large production/VFX environment. Take everything they present with a grain of salt.