No to mention that if you're the first team to import a third_party library, you own it and other teams can add arbitrary cost to you updating it. You have to be very aggressive with visibility and SLAs to work around this.
In a multi-repo setup you can upgrade gradually though, tackling the services that need the upgrade the most first. Can you do that in a monorepo setup?
This also means services can be left to rot for years because they don't need to be upgraded, while all the infrastructure changes around them, which is a giant pain when you do eventually need to change something.
If you have a multi repo architecture you absolutely need both clear ownership of everything and well planned maintenance.
With multirepo setups, you don't necessarily need to update the package for all code at all.
Instead, some newer package completely replaces an old one, with no relation to the old dependency package, or with a dependency on some future one, and both can run at the same time while turning the old one off
No to mention that if you're the first team to import a third_party library, you own it and other teams can add arbitrary cost to you updating it. You have to be very aggressive with visibility and SLAs to work around this.