Wait, they throw them away, not sell or give to employees? I feel like as long as the computer is reset, indeed it is stupid to just throw it away instead of giving or selling it to someone who wants it.

They could resell, but maybe another way to phrase this, tying the screen to the obsolete computer greatly reduces the useful lifespan of the screen. But at that time, DisplayPort didn't do enough bandwidth to have that kind of display externally anyway.