Rust's cutting edge compiler is free, for one thing. I love Ada, but Adacore may well have killed any chance it had of being a commercially viable language (its use declines precipitously each year, even in the defense and avionics industries where it used to be strong).
Plus, Rust has a thriving community whereas thanks to Adacore, Ada has a dying one. Community is critical for programming languages.
But otherwise, Ada is a brilliant and ultra safe language whose safety features go far beyond the memory and type safety that Rust features.
according to wikipedia, their 'free' compiler is GPL without a linking exception. the comparison chart on their page also says it is 'for open source GPL software'.
GPL for an OS is I've thing. GPL for a compiler and runtime is entirely another, since only the latter forces any project you create with it too carry the GPL license.
Plus, Rust has a thriving community whereas thanks to Adacore, Ada has a dying one. Community is critical for programming languages.
But otherwise, Ada is a brilliant and ultra safe language whose safety features go far beyond the memory and type safety that Rust features.
It's a shame.