Ada itself doesn't provide you the same guarantees as Safe Rust. You can use SPARK to grant Ada more memory safety capabilities. However as a language (rather than comments which may or may not be ignored by your Ada compiler) SPARK is from 2014, so now we're close to Rust's age.

I assume that the totality of SPARK's guarantees would get you to the same place as Rust but I don't know.

A big thing which counts against Ada (and SPARK) in practice is that it's not popular. You'll trip over Rust programmers everywhere, two of my friends are getting paid to write Rust, for completely unrelated companies, unrelated reasons, Rust seems like a reasonable fit so those companies picked Rust. You don't see that with Ada and SPARK.