This. I assume it's a similar argument as the one presented in https://loglog.games/blog/leaving-rust-gamedev/

Edit: I just noticed that this article is also writen in the archival reason. I'll leave it here anyway for those that miss it.

Yeah the Rust build time tradeoff for non-trivial programmes is acceptable iff the programme is going to be run at least 100x more than the compiler (or if the programme would be useless without the speed increase).