It is called a paradox because seeing it in action usually catches people by surprise. And this is true whether you're talking about the consumption of coal to power factories, or the consumption of electricity to power computing (and in each case the myriad of new uses that efficiency promoted).

In Science Fiction over and over again the trope was of a giant computer that acted like an oracle. You see that in Asimov's work, in Heinlein's The Moon is a Harsh Mistress and so on. Basically nobody anticipated ubiquitous computing. For instance in the Foundation series you see that a computer run by the Second Foundation can predict the future course of history...and people are calculating their courses with slide rules.

As for the killer app of computing, email, I'm only aware of one pre-1970 work correctly anticipating what it would be actually like. (James H. Schmitz has a memorable scene in one of his Telzy stories where she catches up on her messages at a terminal. He doesn't say "email", but the scene is notable for unobtrusively getting it right.)

For example, in 1964, the ATLAS computer went fully online in Manchester, England. It was the most powerful computer in the world, took up a floor of a university, and the word “supercomputer” was invented to describe it.

The requirements for the Apollo Guidance Computer were to make something with those approximate specs, but take up only 24×12.5×6.5 inches (61×32×17 cm), use 55 watts of power and be ready to fly in 1967. It was a crazy, impossible task.

I’m convinced the AGC was the biggest computing advance after the move general purpose computers.

"Didn't people see the value that cheaper/more electric power will give them back than ?"