Candela is what I immediately thought of when I saw this, and looks like a much more interesting approach that I like both for boats and aircraft. There is no getting around present disadvantage in energy density for batteries vs fuel, even if efficiency helps make it a bit less bad than it'd look like on the tin. But electric drive trains have their own fundamental advantages too in terms of motor power for a given volume, lack of plumbing required, torque, etc. So the more interesting designs seem to be leaning into that to do things that just plain wouldn't be feasible with ICE/turbines. Like with aircraft NASA's X-57 concept [0], electric allows simply having a ton of little motors all over so rather then needing a large wing to try to prevent stalling (inefficient at high speed) they can simply actively force air over a thin wing then shut them all down. Or with Candela they can do interesting things with motors on small foils with the boat fully out of the water.
I'm not expert, but attacking the entire problem space from a different angle rather then just swapping engine for electric and fuel tanks for batteries seems like an interesting way to go long term. Though of course probably makes for more challenging engineering.
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