I’ve wondered if the reasoning behind poor ML usage info has to do with the api endpoints being so profitable that notion of even looking at the code and implementing more straight forward metrics might kill the golden goose.
It's less that and more of the underlying technologies that make up those tools are what surface in the CUR. For instance, you want to know how much you're spending on ElasticBeanstalk. How do you do that? The easiest way is to just get a cost broken down by AMI, then look at the AMIs that are EB (though not the best solution it works most of the time). AI/ML tools do the same. It's hard to break them out (hence why tagging is so important).