Apart from the other advantages of microservice, i dont understand the scaling argument. Sure, microservice can scale better than monolithic, but if you containerize monolithic, it should scale just like microservie, right?
For example, you have 100 containers available and the customer service is used 80% of the time and the product service is used 20% of the time,
- In microservice, there would be 80 containers of customer service and 20 containers of product service
- In containerized monolithic, there would be 100 containers of the monolith app, processing 80% customer service and 20% product service requests
So containerized monolithic would be just as scalable as microservice if i didnt miss anything.
Microservices are about scaling the organization. It's easier to have 500 developers working together if each team can work in isolation, so you have each 5-person team work on their own microservice.
Mostly it's nothing to do with scaling performance-wise.