The steam engine was the great technological metaphor of the Victorian era. The Paradimes of thermodynamics and physics were heavy metaphorical carry overs into Freud’s work. Leaving some of it to be criticised as an overly “Mechanistic” simplification of complex psychological systems.
Most Freud-like is of course his view of Libido and sexual energy. He likened it to a steam engine which redirects through the body or builds up pressure in an eventual need to release the energy.
Of course, it’s always fun to poke at Freud, but this is an interesting tell to The danger of relying on metaphor.