I'm probably going to irritate a few folks, but I do want to half-defend reduced PWC's in *some* cases. For example, where I live, our municipal water supply has alarmingly high concentrations of ammonia and nitrate. Back before I understood water testing, I suffered very high stock losses and disease, while being religious about my PWCs. I couldn't understand why. It turned out my water from the tap was worse than what was in my tank. I've since invested in a comprehensive test kit, and learned to keep lightly stocked tanks with heavy plantings, and perform water changes only monthly to limit buildup of minerals from our hard water. BUT: I test water and maintain filters religiously, and my fish are in good health because I'm still putting in the time/effort to monitor that balance is maintained.
So, less PWCs are sometimes ok, but you still must test often, and it still means maintenance work. There is no excuse to just let it go, and then wonder why your fish die.