This is just so stupid.
This is an obsolete airframe, which should be retired. In a desperate attempt to preserve the system, the military is assigning it the duty that nobody wants.
They do no do this because it is particularly well suited to the role. In fact, it is pretty much exactly not suited to the role. The entire airframe is about high/fast/light. The mission is low/slow/tough. There is no way to insert Tab A into Slot B.
The mission will probably be a success, because bad ground attack aircraft are a heckuva a lot better than no ground attack aircraft. But the mission could be done better and cheaper by just about any aircraft you could imagine.
Except the F-35, of course. The F-35 will be worse at the mission and cost a lot, lot more.
The Mirage-2000D is/was a stopgap. It is the conventional strike variant of the 2000N, which was meant for the nuclear strike role and was hastily designed to cover the delay in the Rafale.
It has one significant advantage over the Rafale: lower operating costs and commonality with the rest of the Mirage-2000 fleet. So you might as well upgrade it.
You don’t need modern airframes to fight ISIS or 3rd world nations. Even some P-51 would do well to strafe The head choppers. Its not like France is going to fight Russia or China.