The examples you gave (DB, JSON, etc) are big enough that there would be decent support for those in Rust. But, your concern is definitely valid for more niche requirements. If your primary concern is availability, stability, maturity etc of a language's ecosystem, then IMHO, you should not choose a language as new as Rust. Rust is currently in the "early adopter" phase, and it is going to go through the same issues (and excitement) that most early adopters do in any field.
Sadly I have seen people get downvoted just because tell the truth . This is really sad for me because we are in HN , we should not have see this kind of bias in place like HN.
p.s. I love rust.
p.s.2 . It is completely logical and most of agree rust is in early adopt stage.
