Big tech businesses are convinced that there must be some profitable business model for AI, and are undeterred by the fact that none has yet been found. They want to be the first to get there, raking in that sweet sweet money (even though there's no evidence yet that there is money to be made here). It's industry-wide FOMO, nothing more.
It will be genuinely interesting to see what happens first, the discovery of such a model, or the bubble bursting.