Sorry, what? Are you claiming that ENIAC was using microservices? That's a claim that needs some kind of supporting evidence, or at least a better explanation.
Sorry, but this is laughably wrong and bears no resemblance to how the history of computing actually developed.
The first systems that could reasonably be described as distributed computing weren’t developed until the 1970s. The object-oriented language Simula was developed a decade earlier.
And those early 1970s distributed computing systems were not, by any stretch of the imagination, microservices. It wasn’t until around the 1990s that the precursors to what we call microservices today appeared, in systems like CORBA, DCOM, and RMI. And the actual term “microservice” didn’t appear until after 2010.
(You may be conflating “service” with “microservice”. Not all distributed networked services qualify as microservices.)
