I've been developing under that understanding since before Fowler-said-so. His take is simply a description of a phenomenon predating the moniker of microservices. SOA with things like CORBA, WSDL, UDDI, Java services in app servers etc. was a take on service oriented architectures that had many problems.

Anyone who has ever developed in a Java codebase with "Service" and then "ServiceImpl"s everywhere can see the lineage of that model. Services were supposed to be the API, and the implementation provided in a separate process container. Microservices signalled a time where SOA without Java as a pre-requisite had been successful in large tech companies. They had reached the point of needing even more granular breakout and a reduction of reliance on Java. HTTP interfaces was an enabler of that. 2010s era microservices people never understood the basics, and many don't even know what they're criticizing.