So they are still at an early research stage. I wish them good luck. Might they take all the time they need to find out whether it is possible to grow a single-crystal GaAs thin film on silicon or not! And when/if they have solved these problems (which might happen or not), they would still have to develop light emitters and light receivers on top of that and find out how to do the opto-electrical integration. That's a very long way to go!

I would think that once POET finally releases its kracken, anyone doing this kind of research, who has 20+ years of research trial and error ahead of them just to potentially approximate what GT has already accomplished, will see no reason to continue. One doesn't need to reinvent the wheel.