Yea except for one problem. You can’t possibly predict what the caldera would do when you interact with it because we can’t simulate it with any model we currently have. You could cause it to erupt in the process of trying to extract energy or cool it

Heh... I wonder how much of the USA you could power by extracting energy from that thing?

Unfortunately it's a park, so you'd have to find a way to do it very unobtrusively. Maybe tunnel and drill into it from outside the park? Call the Boring Company. :)