Those companies are building out AI capacity for a projected demand that might not materialize. There are articles that China currently has an oversupply of AI capacity. Data-centers built specifically for AI workloads on government subsidies are underutilized. Some have resorted to selling off GPUs from datacenters in order to recoup costs.
Like, sure, nobody knows if this will all implode. But the signs sure as hell point to a not so healthy situation.
This is why DeepSeek was so disruptive - not that it was better, but because it did the same thing with less hardware. And other companies have sunk most of their investments into the 'necessary' hardware.