The core patents have already expired. AFAIK manufacturing e-ink displays is still difficult. I also have worked with e-ink displays for hobby projects and yo

The core patents have already expired. AFAIK manufacturing e-ink displays is still difficult. I also have worked with e-ink displays for hobby projects and you’re flipping tiny balls of ink. Unfortunately e-ink displays are extremely slow and it only gets worse if you want colors or anything you might want in a display. E-ink displays look cool and sound cool but really suck to work with.