> n early 1900s ICE is considerably worse than a 2000s ICE.
But how much worse is a early 1900s electric motor from a modern one? I can't find data, but I suspect the first electric motor from the 1830s is more efficient than a modern ICE (even if we assume the ICE is built for efficiency, screw emissions). There is some room for improvement, but there isn't much difference between our best motors and perfection (a carnot cycle by contrast is as best much worse than perfection)
Early electric motors were awful, because there was no good way to control their speed.
For example, DC motors used in some late-1900s trains still had a giant variable resistor in series with their motor, burning away a huge chunk of the power as heat to force the motor to run at a lower speed during acceleration. AC motors weren't much better.
Electric motors only became truly efficient when variable-frequency drive became viable, which was in the 1980s due to semiconductor innovation.
Surely the variable resistor would only have been on the field winding. It wouldn't waste that much energy.
Figuring out where to place it, or how to do this took time. I'm sure some early attempts were really bad.