I believe we have just as many hero's today as at any time in our history and no reason to squeeze the numbers for any reason.
I was in Phoenix, when Medal of Honor Recipient, WWII USMC Fighter Ace Joe Foss was prevented from boarding a plane at Sky Harbor, to give a speech to cadets at West Point, because the airport security had never seen a Medal of Honor, had no idea what it represented, and were concerned he might try to hijack the aircraft with its pointed edges.
Yes, America still has heroes. Many veterans of the Second Gulf War and Afghanistan who performed acts of heroism far greater than throwing themselves on a hand grenade, yet have been denied consideration for the Medal of Honor solely because they survived.
Since Vietnam, no living soldier has been seen as worthy of the Medal of Honor. Not one.