It is absolutely right to compare microservices and monolithic architectures, as they are both systems architectures with important differences that may make one or the other more appropriate in different scenarios. For example, monolithic architectures are considerably easier to develop, deploy and manage, but microservices scale much better. As explained in the Microsoft guide, it is possible to modernize apps with monolithic architectures to varying degrees, but converting to a microservices architecture requires a lot of work and code rewriting.