Not sure why you think ADA/Spark isn't free. There's GNAT[0], an open source ADA compiler that's part of the GNU toolchain, a fairly good book teaching ADA and SPARK[1] by Ada Core, and plenty of tutorials.

Accessibility is really not the problem. The problem is, Ada is an old language that has many similar problems to C: lack of a good package management story, and a design by committee making language evolution glacially slow (though that also doubles as a feature). It also lacks a vibrant ecosystem like we can find in other popular languages.

Furthermore, SPARK in particular takes the concept of safety much further than Rust or Zig do right now, as it allows proving the correctness of a program according to a formal specification. Rust/Zig only care about proving the absence of UB. This makes SPARK much more complex, and thus have a much higher barrier of entry.

[0]: https://www.gnu.org/software/gnat/

[1] https://learn.adacore.com/index.html

Your first link pretty much says it all: barebones website 5 years out of date, no docs, no resources, no community links, no indication that this project is even alive. To top it off the project is named after one of the most annoying creatures on the face of the Earth. This is a marketing issue.

The problem for older languages is that the bar for what's expected of a language has risen substantially. A long time ago, languages weren't even expected to have implementations. Today, not only are implementations expected for all major platforms, languages are also expected to run on phones and the browser, include package managers and library repositories, have a language server implementation and editing modes for all major IDEs, be open source with active development, provide extensive documentation on the scale of a book, and also promote a vibrant and active community. Oh, and to top it off, users don't want to pay for any of that. It's just expected, which is why most languages these days only come out of large tech companies that can afford to fund all of the above with no expectation of profit.

> Your first link pretty much says it all: barebones website 5 years out of date, no docs, no resources, no community links, no indication that this project is even alive.

A better starting point might be http://www.GetAdaNow.com/

Judging the state of affairs there might as well go with ATS. http://www.ats-lang.org/

There's an Ada compiler as part of gcc.

The most prominent project that i know of written in ada is ghdl.

There was at least always the recommendation to only use the version of the Ada compiler released by the FSF as the regular GCC one is/was more encumbered.

Are they not the same thing?

https://en.wikipedia.org/wiki/GNAT