Siri is probably my biggest disappointment on the Apple devices I own. What Siri does works based on Apple’s servers, not on the device itself. While that requires that the device has Internet access at all times, it means that giving Siri a new better understanding of how to give the user what they want is only a software update at Apple, not pushing an iOS update and adding bloat, unless it adds a fundamental change to Siri, like giving Siri the ability to sing.
Alexa and Google Home have become a serious competitor. Apple had the field all to themselves for probably 5 years, and invested very little in improving Siri. It is not like Apple is strapped for cash.