a) Meta is training and releasing cutting-edge LLM models. When they manage to get the costs down, everyone and their grandma is going to have Meta's AI on their phone either through Facebook, Instagram, or Whatsapp.
b) Commoditization is actually mostly happening because companies (not individuals) are training the models. But that's also enough for commoditization to occur over time, even on higher-end models. If we get into the superintelligence territory, it doesn't even matter though, the world will be much different.
c) APIs for GPT were first teased as early as 2020s with broader access in 2021. They got implemented into 3rd party products but the developer experience of getting access was quite hostile early on. Chat-like APIs only became available after they were featured in ChatGPT. So Sam feigning surprise about others not creating something like it sooner with their APIs is not honest.