leave microsoft out of it for now... right now, the only thing a mid-range (7-8 inch) tablet maker should think about is: how does my device beat the nexus 7 2013? and in this case, it doesn't...
It's the same thing with Google's Nexus 5 that utterly destroyed the sales of many other android phones... google can sell stuff at base cost and make profit from the play store... the only companies who have escaped for now is apple and samsung (that microSD and removable battery is a huge win for them).