And that's the problem I've had with large teams of developers. I was on a project with something like 10 scrum teams, and they all wanted to write their own isolated "microservices", so they didn't have to worry about integration.

Of course integration had to happen either way, and it just kicked the can down the road and made it a "dev ops" problem. (Dev ops in quotes because real dev ops wouldn't have been a separate team in the first place)

The point is, you have to integration test, you have to define an API, you have to not make breaking changes, and you have to do all these things regardless of deployment modality.

Beware the disguised call for microservices which is really just a request "not to worry about integration testing".