True, but he never had a peak so to say. From douche back yo damzel in distress to paedo and finally boring no touch boyfriend and back to damzel in distress.
Also I don't think that Mamoru was shafted in the 90s anime. He was still personality wise the same as his manga counterpart. A reserved intelligent young man who is a valorous hero and a loving boyfriend. Not to mention he saved the Senshi's collective bacon numerous times. He even defeated Beryl in her first form in the 90s anime. The main thing that would have made him better would have been to give him an attack like in the manga with Tuxedo La Smoking Bomber.