it doesn't unravel the underlying complexity of what it does... these alternative syntaxes tend to make some easy cases easy, but they have no idea what to do with more complicated cases

This can be said of any higher-level language, or API. There is always a cost to abstraction. Binary -> Assembly -> C -> Python. As you go up that chain, many things get easier, but some things become impossible. You always have the option to drop down, though, and these regex tools are no different. Software development, sysops, devops, etc are full of compromises like this.