rustup in particular is well-behaved. It installs itself in a single directory, without modifying the system, apart from PATH which it warns you about, lets you

rustup in particular is well-behaved. It installs itself in a single directory, without modifying the system, apart from PATH which it warns you about, lets you skip it, and when it does it, it does with care. OTOH many distros don't take care to build and package Rust properly. For example, Rust patches its version of LLVM to avoid known bugs. The particular combination of Rust version + LLVM version is most tested. Distros that insist on unbundling build Rust with a stock LLVM that doesn't have these bugfixes, and often is an older version of LLVM that hasn't been thoroughly tested with Rust. Then there's the mismatch of upgrade approach between the Rust project and most distros. Rust uses an "evergreen" (Chrome-like) approach to upgrades, in which the focus is on making upgrades seamless and not breaking anything so that they can be small and frequent. Most distros prefer infrequent big upgrades, so they package unusably old and officially unmaintained versions of Rust for no good reason.