I'm gonna try to keep this short, which for me is anything under 5000 words...
I grow weary of people claiming that certain products or techniques were invented recently, and that much adulation and praise must be heaped upon those who "invented" them. In reality, there is only so much that can be done while shooting or designing things that shoot. This leads to overlap, current or historical.
Take muzzle devices. The way some people tell it, the Battle Comp is the greatest thing ever. A few other companies came along and copied their design, and they all suck and the Battle Comp is the best.
Ignoring the fact that the BC pushes the muzzle down and is therefore not the greatest thing ever, it was predated by the KAC Triple Tap, which is a few years older. But if we look way back, we see that devices quite like the Battle Comp existed before anyone involved with that project was born - take the muzzle device of the German FG42, a WWII-era automatic rifle, for example.
Or shooting techniques. I grow weary of people acting like Magpul Dynamics invented the "thumb over barrel" support hand method. I'm kicking myself for not saving the video I saw depicting an SF soldier in Vietnam shooting an M16 on full auto in Vietnam with a classic "thumb over handguard" shooting method, and doing very well at controlling the weapon, too. But here's an image from a WWII documentary about Iwo Jima. Not only does the Marine depicted have a "homemade" vertical grip attached to his Thompson, but he appears to be wrapping his thumb up and over the barrel (or at least forward along the barrel on the handguard).
I'm currently doing some testing with steel and brass cased .223 ammo - imagine my surprise when I found a 50 year old US military study about steel cased .223 that discussed several of the things I "discovered" in my testing.
Without historical knowledge or a frame of reference, any new discovery to us seems like an absolutely new discovery to everyone. While science has certainly moved us forward in some ways, that "new" product or technique may not really be all that new.