I've worked on large monoliths (100k LoC is not "large") and have a strong preference for them because I've also worked on large microservice architectures. A monolith with a strong architecture and development process works well. Microservice architectures are often a fig leaf for poor architecture and development process, while introducing new problems and increasing development effort. It is always less expensive in the long run to fix the architecture and process problems than to sweep them under the rug with microservices.

I understand that microservices often become necessary in organizations when they are constitutionally incapable of addressing the root issues directly. But we shouldn't normalize introducing microservices so that we can ignore poor architecture and process, which underlies the majority of cases I see.