Doesn't matter if it's useful if it's too expensive to use for the majority of use cases it has. Voice assistants like the echo are useful and people like them. However they aren't particularly profitable because people hate when they get monetised and won't use them that way.

AI is likely the same, most of the stuff it's being used for... even vibe coding where it's been hyped to the moon and back, probably aren't viable when the total cost of the compute needed for training and running are actually been charged for.