An air traffic controller messes up and they risk hundreds of lives and 100's of millions of dollars in property. That's a high high-pressure workplace, Tech is just a combination of greed and poor managment.
High pressure describes an environment that can exist anywhere, independent of the decisions to make it that way. I like to listen to a famous controller at JFK. I detect no pressure in his voice. Every line of work has a share of high pressure environments. There are likely many people who could say "You want high pressure, try teaching pre-school!"
You're mistaking what it should (or rather shouldn't) be with what it actually is. It shouldn't be high pressure because the stakes aren't that high, but it is. The poor management is the causal reason.
Ehhh. Zooming out this far just makes the phrase meaningless in the context of tech, which seems counterproductive since as you may have noticed we tend to discuss tech around here.
Fine. Writing air traffic control systems is tech, and is pressure.
The difference is artificial pressure driven by concerns like "I will look bad to my boss" or "or EPS might dip a fraction of a present", as opposed to "people will die".