I think I could not disagree more. Coupling and cohesion are problems you will have, regardless of the repo approach you take. But a mono-repo gives you a host of incredibly beneficial advantages, especially for larger organisations.
Any downstream library team can instantly tell if their change has broken any upstream users because a good CI system will just automatically run all tests of all relevant projects. That way a library developer can either iterate until all projects depending on it are green, or the library developer can even proactively change all dependant projects and roll all fixes out in a single atomic commit.
This has proven incredibly beneficial to our development speed and the number of avoidable code conflicts that crop up.
Any downstream library team can instantly tell if their change has broken any upstream users because a good CI system will just automatically run all tests of all relevant projects. That way a library developer can either iterate until all projects depending on it are green, or the library developer can even proactively change all dependant projects and roll all fixes out in a single atomic commit.
This has proven incredibly beneficial to our development speed and the number of avoidable code conflicts that crop up.