You aren’t wrong… But everything with extended use needs to be maintainable. Making a change in 5 places sucks.
Plus, that’s what open-closed principle is all about. Instead of adding additional functionality to current working code, you extend and modify.
Micro services alone aren’t enough. You have to have proper observability and automation to be able to gracefully handle the loss of some functionality. Microservice architecture isn’t a silver bullet, but one piece of the puzzle to reliable highly available applications that can handle faults well