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The Hyperloop was always a scam
(www.disconnect.blog)
This is a most excellent place for technology news and articles.
I'm assuming it's probably technically possible, just ridiculously expensive to build and maintain, with way less throughput than a train.
Again, maybe it is but you can't really be sure until you design it, estimate the cost, try to lower it by modifying the design and if it's close try building some prototype to test it. People keep talking like you can evaluate design like this on a napkin. That's just not how engineering works.