I think it's easier for Rust (and other languages such as D, Crystal), because they started from scratch. Cargo is accepted as the way to build and distribute stuff on Rust, full stop. There are no endless debates whether Cargo should be used, or something else.

Meanwhile, in C/C++ world, build systems are a mess. You have so many tools. Some folks just use what IDE provides, e.g. MSVC solutions. Some people use CMake. Some people have their handcrafted Makefile solutions. Sure, it works on their platforms, but it's very hard to make it portable. With Cargo and similar, you just go "cargo get" (don't know the exact command, don't use Rust) and you can expect the packages to download and build as needed.