That "big ol' gun" is not overkill at all. Sure, it's a tank killer, but there are other targets out there where that gun will/has, proven quite effective. Plus all the other ordinance that it carries. Sure, we can use a 30 cal, and carry way more rockets, and bombs. But that big 30mm negates the need for some of the more expensive rockets, and bombs. The A-10 has proven it's ugly self to be somewhat indispensable, in the area of close air support of ground troops. It does things that the other jets just dream they could do.
That big 30 mm gives the pilot all of 16 seconds of firepower. How's that gonna work out against a 10, 20, or even a 100-drone swarm?
Sure, a single 30mm hit will destroy a drone. So will a 20mm. So, probably, will a .50 cal round. If you're got a swarm coming in, caliber has probably less importance than volume of fire. Which the A-10 can't provide.
And don't forget... "Amateurs study tactics. Professionals study logistics."
How's that logistical tail holding up for that 30 mm gun? Some sources are saying we've fired off 80% of some types of ammunition into desert sands. Remember, the only other place to find it is the Dutch Navy.
Contrast that with 20mm, which is much more common in the international market. Running short? See if Great Britain can send you a few thousand rounds under the table. Offhand, though, you can't going to get much help from the Dutch, I think.
Sure, the A-10 can carry lots of bombs. So can lots of other aircraft.
The A-10's success in the Middle East is due to one thing: It's there. If the Air Force still had A-1 Skyraiders, the press releases would be ballyhooing how they'd been whomping drone tail. If we'd bought Piper Enforcers, we'd be bragging on how a 80-year old design is still able to fight.
Have they *looked* at adding gun-pods to the A-10? Something that'll give them more staying power?
Shoot, if one owns a pizza parlor, you *could* use a cement mixer for deliveries. But there are more efficient ways to perform the job.

Ron Wanttaja