But what's the threat model here. Does it matter that the Rust STD library doesn't expose say "Regex" functionality forcing you to depend on Regex [1] which is also written by the same people who write the STD library [2]? Like if they wanted to add a back-door in to Regex they could add a backdoor into Vec. Personally I like the idea of having a very small STD library so that it's focused (as well as if they need to do something then it has to be allowed by the language unlike say Go Generics or ELM).
Personally I think there's just some willful blindness going on here. You should never have been blindly trusting a giant binary blob from the std library. Instead you should have been vendoring your dependencies and at that point it doesn't matter if its 100 crates totaling 100k LOC or a singular STD library totaling 100k LOC; its the same amount to review (if not less because the crates can only interact along `pub` boundaries). [1]: https://docs.rs/regex/latest/regex/