Amazon, Microsoft, Google and Meta are still proceeding with large data center buildouts for several reasons:
The surge in AI compute for reasoning and AI agents requires more compute and the increased efficiency enables more value to be delivered. Jevons paradox (economics) occurs when advancement make a resource more efficient to use but the effect is overall demand increases causing total consumption to rise. This was seen with cheaper personal computers meant the demand for computers increased 100 times from tens of millions to billions of units. The top 4 companies plan to spend $310 billion on AI infrastructure and research.
Deepseek came out at prices per million token that was far cheaper than OpenAI but OpenAi and Google Gemini have competitive and even better pricing.