Higgs

Could use the energy harnessed, to power windmills.

No reason to think not, if the combustion was set up from the start to use hydrogen and not an old carbon contaminated system converted to run on hydrogen. Can't imagine any organisms surviving the process. The human end user probably would.

Sounds like more systems and control being taken away from the owner. I don't really mind the diagnostic stuff most present day cars have, but that's it.

In ordinary woodworking/frame making terms, that would be true, but in the context of this area by the window, this piece provides no strengthening to the structure. It would be unusual in boat fit outs for this piece to be made part of the wood battening at the early stage, which is when this would be fitted in your example, as a piece. The piece in these areas is only cosmetic.

They're there just to fill the gap between the usual rectangular wood framework of the inside, and the curvature of the window frame corner. The triangular type piece in most cases does not extend to the frame edge that meets the glass. And rather than a simple triangular shape, it is usually slightly shaped and decorative, thus, making it less obvious that it is just a gap filler.