That doesn't seem relevant. The article isn't asking "is C++ better than rust?" or trying to make qualitative judgments on overall "worth" - it's an exploration

That doesn't seem relevant. The article isn't asking "is C++ better than rust?" or trying to make qualitative judgments on overall "worth" - it's an exploration of one area, an apples to apples (as close as possible, of course) comparison of compilation speed given a set of optimizations and constraints. Rust may do more analysis, c++ may have other tooling, but that's not relevant - the speed is the speed. Sanitizers should primarily impact runtime performance anyways, but that's moot.