This will be true if every team handling their own microservice will treat documentation like a real API like product and make it understandable, concise with clear examples. Also it needs a proper way to accept/debate bug/feature requests.

But in my experience this is not happening. There is documentation but it is usually auto generated and most of the times out of date.

So instead of reading it and trying to figure it out oneself it is more simpler to just contact the developer thus => more time spent in communication.

The same when I need a new feature from their API I setup a meeting as usually sending an email or creating a ticket does not guarantee a response => so more communication.