First of all, Rust is relatively new so this tells me that the codebase is likely new.
Secondly, I think rust tends to attract smart people who like programs to be small and fast. Case-in-point meilisearch is a simple, single binary download.
Both of these together indicate that a project has a higher chance of being freshly written code, by smart people, that is small and fast.
Before I get a bunch of we’ll actually’s, I’m not saying these things are true 100% of the time.