Behind paywall, but I believe it has already been leaked that this was Elons way of sabotaging public infrastructure projects that he considered a danger to his car company.
Honestly, I would just call him malicious, not paranoid. He has made it clear that he hates public transport, as in the idea of using it (in that it is crowded and such...). This is of course funny because we all know that Musk has never in his life used a regular city Bus or even a train. I think it is safe to assume that he would do something like this not for monetary profit, but simply out of spite.
We are talking about a guy that pays tens of thousands of dollars just for the attempt to discredit and harass a rescue diver he doesn't like... [1]
[1]: https://www.bloomberg.com/news/articles/2019-09-16/musk-reve...
I’m skeptical, and this CNBC article quotes Elon refuting it:
> According to Musk, he does, in fact, "actually love trains, most subways and London buses." From https://www.cnbc.com/2017/12/21/elon-musk-versus-twitter-on-...
What Elon actually said is that if California (in his opinion the most advanced place in the world) would invest so much in a system, it should be world leading and novel.
I think Musk is wrong about that and Hyperloop isn't actually better then HSR but there is no reason to just make up a conspiracy.
And being for cancellation (something money people want) of HSR is not the same 'hyperloop was made up as grift to get HSR canceled.
"ἡ γλῶττα λανθάνουσα τὰ ἀληθῆ λέγει"
- Μένανδρος