Sometimes old versus new effects this. For example in Rust the language improves so fast I've literally had a 3 month old rustc be unable to compile a rust program (SDR FFT thing) because it used a new feature my 3 month old rustc didn't support. As I continued to encounter Rust projects this happened a few more times. Then I decided to stop trying to compile Rust projects.
Right now the dev culture is mostly bleeding-edge types who always use the latest version and target it. As Rust becomes more generally popular and the first-adopter bleeding-edge types make up proportionally less of the userbase I expect this will happen less. Bash still gets new features added all the time too; it's just that the type of developers who chose to write in Bash care about their code being able to work on most machines. Even ones years (gasp!) out of date.