Based on the performance bump we saw from the 1080 Ti, I don't think it's fair to say that nVidia's slouching when it comes to GPU performance. Pricing, sure, they could use more competition. But something like 4K/144 is a seriously enormous amount of processing to do. The DisplayPort and HDMI interfaces themselves had to be updated to transfer that much data. I'm amazed we got 4K/60 out of GPUs as quickly as we did. Give it another generation and we should be hovering around 4K/144. But you ask why there's no 4K/144 gaming monitors coming out yet, and this is why. There aren't any 4K/144 GPUs out yet, either. And it's not because any particular company is stagnating. It's because pushing that many pixels to a monitor is a huge, huge task.