From the tweet in your linked post:
> This could help OpenAI give free users more generous usage and features, while users on paid plans stay ad free, which fits with the high costs of running ChatGPT and the revenue they expect from shopping and ad related features
They will put ads in the paid ChatGPT tiers. That is an absolute certainty. The only question is how long will they tolerate un-advertised eyballs on paid plans.
I could see ChatGPT search results having affiliate links for shopping stuff even for fully-paid users.
There's a lot of competition in this space, so we'll see what users tolerate. But it's going to be tough getting around the fact this stuff is expensive to run.
Things like this are only 'free' for a reason.
What's expensive is innovating on current models and building the infrastructure. My understanding is inference is cheap and profitable. Most open source models cost less than a dollar for 1 million tokens which makes me think SotA models likely have a similar pricepoint, but more profit margin.