It boils down to this: If you support the direct will of the people in choosing a candidate, you probably like RCV. If you want the party to have significant influence in choosing a candidate, you probably don't like RCV.
It is possible the Democrats are realizing that their establishment selected candidates are not competitive against modern Republicans.
It's also possible they are considering somebody more radical but want plausible deniability about how that person came to be elected.
Or it's possible they are just out of ideas.
Or maybe all three...
Okay but that's more talking about the benefit of a 240v system. The question here was the benefit of the giant UK plug. Personally I would argue that 240v to every receptacle is not a major benefit, because very few devices require 3kw+. And in exchange you get a somewhat more hazardous system.
I am curious if homeowners in NZ are allowed to work on their own wiring? Here in the US you are...