The most practical uses of recursive functions are those that cannot be easily eliminated. For an interpreter, it could mean dozens of functions all calling each other in a pattern determined at runtime.

The issue used to be with LLVM, yes, but that appears to be solved (see Clang's 'musttail' attribute). Instead it's more about language design. Constructors, destructors, and all of the fancy language features Rust has must work with this new feature, with no changes being visible elsewhere.