A few have tried to compete over the years, none have really managed to ramp up production and compete from my understanding. I believe there are some chinese firms making smaller panels now, mainly used in electronic shelf labels for stores.
From my understanding most of the patents for the foundational tech have expired at this point. I believe the panels are just generally very difficult to make, with difficulty ramping up further as panel size goes up, presumably the yield is fairly low.
Competition explores completely different technologies: Daylight DC-1, Reinkstone, ChLCD e.g. from Iris... but either the tech isn't good enough to generalize or be cheap (the later), or the niche economics don't allow the inventors to keep investing (the two first).