Simply not true. Modern Army aircraft such as the AH-64A/D and UH-60A/L have ballistic shielding and redundant systems to take some major hits and, at least get to the ground safely, if not fly out of harms way. The AH-64A aircraft engaged during Operation Anaconda took some heavy hits yet continued to support troops on the ground. One had it's TADS bucket (front sight) blown off yet remained on station to provide fire support. Another one took an RPG round to the # 2 Engine and transmission. The crew was able to fly the aircraft a safe distance, filled the transmission with extra fluid, then flew it 38 minutes back to Bagram Air Base. They landed safely with a completely dry transmission.
Yes, the HIND aircraft are heavily armored, but are not nearly as manueverable. They were designed to support Soviet style mass attacks against NATO forces. A-10's are great at what they do, but are even more effective when working as part of a Joint Air Attack Team (JAAT) with attack helicopters and other fire support assets.
For all of it's faults (and bad, undeserved press) the AH-64 is a great aircraft and quite lethal.
Now this is a flying tank!