Schema evolution is just as big of a dependency hell as managing direct library dependencies. With a monolithic architecture, a lot of those concerns are contained within the context of a single repo, and can be tested much more easily than with many repos.

A library API can rely on versioning and account for schema evolution too. Even different versions can coexist if you decide that's important from the beginning (what is the same requirement as with services).

The only real difference is that services have a slow serialized network interface that fails 4 or 5 orders of magnitude more often than libraries, but can migrate over memory domains.