Why do you think Canon should stop APS-H sensors? What is the interest for Canon?
Because the 1.3x sensor is a lesser sensor than FF. This means that:
- if Canon charges more for the 1DIV than Nikon for the D3s, Canon will be overcharging for a lesser camera
- if Canon charges less (as is the case today), the long term perception will be that Nikon is the premium player in the market and Canon is the discount/second grade player
As you can see, Canon has no choice but to abandon the 1.3x format - unless they want to be the perceived as the discount/second grade player in the market for pro cameras.