What's working for them is having a huge amount of resources and very good people to design a cutting edge agent harness, RLHF the hell out of their models, and build out a tremendous amount of inference capacity. I'm sure their process for making code changes in any of their client apps is very fast, but a TUI built around a chatbot is also not a particularly complicated application. So yes it's working for them, but the vibecoding that they are selling is clearly not what they are doing in practice.