We could have had the steam engine thousands of years ago, but slavery was the reason for the historical delay.
Without the creation of the steam engine we wouldn't have had the industrial revolution that catapulted us into the modern times full of assembly lines, factories, and cheap goods.
Thank goodness for those brainiacs back in the 1800s. Too bad they didn't come up with steam power—you can thank the ancient Romans for that!
The earliest known notation of using steam as a power source was when Heron of Alexandria described steam powering devices used to open and close gates, doors and blow horns.
However, the use of the machines was just used as a spectacle or novelty. Though we used it for many practical reasons, the Romans had a different, cheaper power source: slavery.
It's very possible that the development of things like the steam engine and other scientific discoveries were hindered due to slave labor. Without the need for quicker, easier, and cost effective labor there was no need to develop anything new.
Just count this as yet another notch in the “bad” column for slavery! It's a shame it took so long for miraculous breakthroughs due to nefarious reasons.