That assumes that holding perceived performance steady while letting compute consumption get cheaper saves enough money, quick enough. If voice assistants were

That assumes that holding perceived performance steady while letting compute consumption get cheaper saves enough money, quick enough. If voice assistants were losing $10 billion a year (made up number) in 2013 and bringing in zero revenue, then it is easy to see why a decade later they would have less compute allocation now than they did back then, even in absolute terms. If the revenue is near zero, then the spend on compute will be near zero too, after everyone figured out that it wasn't going to win some AI battle for all the consumers. If they are not willing to set money on fire for no measurable benefits anymore, then compute will tend to zero over time.