Aussie, Hyperloops sound like scifi, but they're really not that far off. Really, it's a question of logistics, not technology, and global construction logistics is more dependent on politics and economy than anything else.
https://en.wikipedia.org/wiki/Hyperloop
On the subject of an issue on them, I would agree though that it treads too much of the same narrative ground as the high speed rail issue.
On the other hand, a consequence issue that chains off 634.1 wouldn't be a bad idea. That option currently picks up a whopping 70% of players who answer that issue, so it'd be a sensible one to chain off.
The consequence issue could look at the propositions for the high speed rail service, and ask you to pick between the available technologies (hyperloop, elevated magrail, bullet trains using existing rail gauges.)
The trick here would be making an issue that is technically well informed, but which isn't JUST about speed vs cost. For example, a bullet train approach could allow the same funds to provide high speed rail links to more cities and outlying regions, giving more economic equality. A hyperloop could encourage the growth of associated tech companies, but be more vulnerable to sabotage.
Lots of ways to develop that narrative, but it wouldn't be an easy write.
