10 people managing a single "micro service" does raise a red flag to me as well. It may be normal based on the complexity, but my first thought is, why is the codebase require so many people to maintain and add features to? Are they just adding features like mad, or something squirrelly in there where most modifications take a lot of man hours?
"Micro" in this case relates to the services scope, not its operational footprint.
So if Netflix has a "User logon" service, and a "payment processing" service, used across their clients clients you might be looking at a couple of "microservice"s with hundreds of related employees. Imagine services for Googles search autocomplete, ML, or analytics...
As the article states the "micro" aspect is mostly in terms of deployment responsibility, freeing those 10-1000 employees from thinking about the totality of Googles/Netflixes' operations before rolling out a patch :)
If "micro" refers to the scope of the service (i.e. very limited feature set), you might still need a team to run it, if the service has to handle a very high volume of transactions or provide very low latency, or both.
