The key is enabling maximum developer leverage - and one aspect of this is to get rid of as many systems errors and inefficiencies as possible.

I think build systems and internal code management schemes are large interconnected systems. It feels fairly pointless just to expose one facet of the entire systems since the total system encompasses all of the individual entities dealing with the codebase - including developers, platform - the whole works.

For example, I see no overhead in my daily work from the fact that our codebase is split to several libraries with dependencies through explicit built release versions. On the contrary,there monorepository would be just horrible.

So, before saying X is great one should firsr define what type of software is built, what is the specific toolchain, what are the specific configurations, how many developers modify the same codebase frequently, and so on.