I would say it's the "electric blue" era of 1997-98. There was just so much weird stuff going on at that time. Not just the power change but the blue alien taking Superman's costume and they were clearly out of ideas. The only good thing about it was when it was over and they did the whole "every era of his history" thing for his 60th anniversary. I understand that it had something to do with some change in copyright law that started the whole Siegel family suing for the rights mess we are still dealing with today which somehow makes it even worse. The second worst would be the Brainiac 13 thing where they changed Metropolis to match the one in the cartoon.