that is complete bullshit. The useful energy extracted from the humans would necessarily be equal to or less than the energy expended in keeping them alive
first of all it's the future and they some how figured out how to make virtual reality indistinguishable from reality. pretty sure all current science goes out the window. and machines would do this better than we ever could
How far have we really come since then though? Airplanes and automobiles were already in production, energy was being used, modern physics and medicine had been/was being developed. The framework for our scientific advancements were laid out for us in that era.
I find one thing common around the tech boom era is that people vastly overestimate what we will be capable of in the next few decades. You can look back to movies created in the 1980s that portray our time (>2000) owning flying cars and hovering skateboards. Viewing those movies now we think "how silly" yet we do the same thing when we talk about interstellar travel and weather/tectonic control within the next 100 years.
I guess time will only tell.
in 50 years we went from inventing the airplane to dropping a nuke.
things are getting smaller rather than bigger. probably huge advancements in biotech/engi.
star trek did have a phone of sorts, but our phones ended up becoming exponentially better than that.