Is Jarrell "Big Baby" Miller America's heavyweight king?

Boy did I call that one wrong!

 

Miller is the most proven but he is 37. I think Joshua Edwards is the most talented and is only 26 but he is totally unproven

 

What has happened to the American heavyweights, Wilder and before that it was Briggs, that's a long time to produce only two champs. I know Klitschko reigned for years but even the contenders haven't really been anything special relative to the earlier eras. Actually we have Stiverne and Martin who were very poor quality champions. Did Briggs even fight for that belt too? Stiverne is Canadian I read anyway.