That's a fair argument, but from personal experience HiveQL has some pretty major features added on that make it "have such power and support so many use cases"

That's a fair argument, but from personal experience HiveQL has some pretty major features added on that make it "have such power and support so many use cases" in a way that other common variants like the one used by MySQL doesn't. A lot of HiveQL's power comes from extending the language, not from the use of a small set of timeless features.