This probably signals the beginning of the end for OpenAI. Eventually all of the AI chatbots will have Ads at least on the free and low-cost tiers. But there's a strong incentive not to begin enshitification until the number of competitors has dwindled, and an oligarchy has been established. Google, Meta et al. can afford to lose money on AI for a long time, because they have real revenue from other business products; they can stay Ad free until the small-fry go bust.