Despite my critical views of the TBD, I will say though Apple shouldn't give up on this product segment. Monitors in general could use some innovation, especially in regards to panel thickness, back light bleed, warm/cool light uniformity, and overall design.
Abandoning the TBD also puts products like the Mac, Mac Mini, and especially the new Macbook (with it's single port USB-C configuration) in a precarious position. Apple is all about the ecosystem, so to not have an in-house external display option for these products seems a bit odd.
I'd love for Apple to explore a 5K OLED monitor, with a razor thin screen design and curved aluminum base. Add in support for TB3 over USB-C. Allow for all the latest color support like full Rec 709 and DCI-P3 for professional work. There's lots Apple could do to re-up the TBD as a leading, professional product.