A MOAB apparently has the equivalent of 11tons of TNT. A drone carrying a grenade has up to 180 grams. So you need about 61 111 drones to deliver the equivalent explosive. At that point it might be cheaper to just bring the MOAB.
A MOAB can only blow up one target, 60000 drones can do a lot more damage. Just ask Russia how many tanks they have today, from the thousands they had a few years back.
61111 * $200 is only a little over $12million. The plane to deliver the MOAB is more than that. Also, why does it need to be a grenade? Why not deliver C4 or other explosive material?
The 200$ drones have a couple of kilometers range at best. You won't deliver them from 400 km away. You still need a delivery vehicle. But this discussion went off the rails, it's obvious fantasy land at this point.