The cycle of weights

It's something I've been thinking. The Heavyweight division and the Welterweight/Middleweight have been rotating the attention of the boxing world for a long time. Back in the 40's the HW was at the center with Joe Luis, than WW/MW with Robinson, back to HW in the Ali era. The fabulous four took it back and the 90's were all about the heavies. In the last years, Pacquiao and Mayweather were the biggest stars in boxing, operating more on the WW. Now the HW seems to be resurging with the Wilder-Joshua rivalry and a lot of good prospects coming. Can we say the Heavyweight is back or too soon? And how can this comeback impact boxing as a whole, since the Heavyweight division is the more appealing for the casuals?