I'm not sure languages without a package manager being the default are nearly as bad.
When it is trivial (like running a single command line or a single line in a file like cargo.toml), having a proliferation of dependencies is so easy it almost becomes guaranteed. But in languages like c++ where not everyone uses them (even if several PMs exist) adding a dependency to a library is a much bigger deal as you either have to use something like git submodules or manage them yourself OR make any user of your library go get the correct versions themselves.
> I'm not sure languages without a package manager being the default are nearly as bad.
The autoconf or cmake list of included libraries for many non-trivial C++ projects is usually just as long as stuff in Cargo, especially when breaking up Boost, Qt, or other megaframeworks into individual libraries.
They do "make any user of your library go get the correct versions themselves" but that has been far less of a problem this century thanks to OS package management.
The thing is, when adding dependencies _isn't_ trivial, you end up vendoring. You aren't gonna thoroughly test your command line parser if it is a very small feature of your overall project. A dedicated command line parser lib will (more likely than you in this case) thoroughly test their implementation.
I think it's important to figure out what you're comparing though.
A language that makes it easy to pull in dependencies also encourages breaking code into separate modules.
Languages that make dependency management hard tend to have larger, heavier dependencies. Two dependencies in such a language are more likely to have duplicate functionality between them, instead of sharing the functionality through another dependency.
Is it better to vet many smaller dependencies, or fewer large ones that likely duplicate a lot of stuff? It depends on what those dependencies are.
I don't think just looking at dependency counts is that useful. Many libraries that would be a single dependency in other languages are split into several because they are useful on their own.
When it is trivial (like running a single command line or a single line in a file like cargo.toml), having a proliferation of dependencies is so easy it almost becomes guaranteed. But in languages like c++ where not everyone uses them (even if several PMs exist) adding a dependency to a library is a much bigger deal as you either have to use something like git submodules or manage them yourself OR make any user of your library go get the correct versions themselves.