For example, a developer asked to change the payments processor from the Stripe API to the Adyen API needs to know about:

1) credential scoping across microservices and test environments 2) impacts on billing, tax management and customer support 3) the organisation's approach to external dependencies (e.g do they use some kind of internal registry)

Microservices don't inherently make this kind of change more difficult. A well isolated payments microservice might even help. But having hundreds or thousands of microservices spread across several code repos makes it quite difficult to figure out how your change will affect other services.

I acknowledge I've picked an extreme example that wouldn't be asked of a new hire. However, smaller versions of the same challenges will happen in the smaller API upgrades & migrations that make up a big part of what the average CRUD developer does.