Actually this force is to create the much needed umbrella for military intervention. Saudi Arabia for example doesn't have the US umbrella that Israel has that it can take actions unilaterally and have a veto in the UN to save it, or Assad in regards to Russia, its mostly on its own in foreign policy out there and rapidly losing influence in the west. But having an Arab coalition umbrella means that other countries would have to think really hard about taking actions against such a large group.
That's good I supported joint military co-operation and missions all along. Even when Iraq gets stabilized they will be partially responsible defeating IS on the bordertowns and help export the fight all the way up to Al Raqqa. Just a matter of time.
As for ground forces, do you think the Arab states unaffected by war are waiting to send soldiers, of which some will end up dead and captured ? It's a price the west has been willing to pay in many wars but it looks like the current Arab leaders lack the willingness. I've read about the UAE intervention in Afghanistan but that is nowhere the level of danger when sending soldiers on the front to recapture cities together with local forces.