Moving goods by train is highly efficient.
Moving people is not, maybe.
I love to travel by train, like the slow non rushed travel. The travel time by train just has to figured into the length of a vacation.
If you are talking about moving people at high speed across long distances, I agree, we have the tech to do it, and other countries already have done it.
I watch Top Gear and they do a lot of races across Europe car vs different public transportation. So far, I don’t think public transportation has won yet.
Even flying a small private plane from the south of France to London was slower than the drive.