That Roz flurry gets used over and over but the reality is in that most of his modern fights (aside from Stipe 1) he was able to avoid getting hit while landing his own shots. If you're just a brawler you're going to generally have to walk through hell to land your shot, like Roy Nelson for example.
Ngannou beat Stipe in the second fight not only because of power, but he also generally out struck him. Granted he looked almost helpless standing against Gane, but there is the possible injury factor in that one, in addition to Gane just being that good of a striker for a HW.