I enabled on my early 2015 MB Pro 13". It works for both wire and wireless option. However, it seems graphic resolution on iPad is terrible, like a bad jpg graphic. Maybe need to reduce the resolution on Mac?
It kind works. With my early 2015 MBP and 1st gen iPad Pro. However, when I moved mouse to iPad extended desktop, everything get pixelated like not enough power to refresh the screen. Any content with movement, just pixelate the whole screen on iPad. not sure if its the iPad couldn't handle it or the 2015 MBP couldn't. Maybe that is the reasons the 2015 MBP is not supported under official release. Wish there are more users testing those with different configurations