To make it in todays boxing do you need to have the big amateur background?

Boxing seems to geting taken over by alot of european, cuban and some american fighters who all had huge amateur back grounds? are the days gone when fighters like dwight muhammed qawi, Jeff Chandler, Billy Conn, Harold Johnson, Joey Giardello, Pipno Cuevas, Jose Luis Ramirez and Salvador Sanchez, Charles Brewer, Mathew Sadd Muhamed, Boogaloo Watts and Tim Witherspoon gone when you could have none to very little amateur fights and still become world champion? Former lightheavyweight champion Harold Jonson once said that you can have a 100 odd amateur fights or you can have none if you can fight you can fight. Your thoughts on all of this?