My expectation is that the no-name hobbyist products (with no clear company to sue) will come first, people will buy them, and then major manufacturers will see them and want to get the hardware into their own products too, at which point they'll probably get interested in licensing Apple's patents. Which means the resulting branded products won't cost $3, but they won't be $1000 either.

I don't expect Apple would willingly license their patent to their competitors in the mobile space (who, after all, would just want to slap a FaceID-equivalent feature into their own phones); but they'd probably be interested in licensing it to e.g. electronic door-lock companies, or action-camera companies (add a "depth" track to your video), etc.

My guess is that rather than the Kinect, what people will probably be buying 2-5 years from now for "commercially scalable" projects is an LG USB webcam that has Apple's miniaturized sensors embedded, and is using the (by-then-standardized) no-name Shenzhen remake of Apple's face-recognition ML-accelerator core.