This idea that developers suddenly lose credit for their great works when they inevitably start producing bad games is something that I don't agree with.
Almost every great named developer turned into ass and released a flop at some point. People like Will Wright, Warren Spector, John Romero, Peter Molyneux, John Carmack, Keiji Inafune, Tomonobu Itagaki, Cliff Blezinski, Yu Suzuki and so on were all considered near untouchable legends at some point, and all of them ended up releasing something garbage that either damaged or completely killed their career.
Molyneux was great, but he, like everyone else, ran out of juice. The only difference is is that his smug demanour and lies made his fall more significant.