I mean we're all ugly bags of mostly water running around on a rock planet inhabited by living water beings of various construction, all ingesting and excreting water, and we've figured out how to use water (usually with fire) to make rocks do interesting things.

So every time we figure out a new interesting thing for rocks to do, we'll either do it with water or do it to water.

Of course here in a bit we might make rocks smart enough to start doing stuff to/with rocks and fire, which might make all us water beings obsolete.

There are a million efficient ways to make heat and tons of new development to be made in making heat in new ways. There is relatively very little development in turning heat into kinetic energy and then electricity when size and weight are no object. The combined cycle turbine is incredibly efficient and is likely to continue to be ubiquitous in power generation for some time.

Why don't they just use an induction stove, are they stupid?