Just like Lisp and Smalltalk still have their commercial offerings available.
Naturally communities that want to be payed for their work, while refusing to pay for their tools aren't aware of such offerings.
I imagine Adacore has a larger share, but have no data to back that up.
Adacore is (I'm guessing) the main vendor for lots of aerospace projects with deep pockets that aren't going away soon and it runs on mostly anything GCC runs on. They're also expanding their business into areas where cyber security is a concern.
I think its very telling that real-world JOVIAL code bases are being converted to C, not Ada. Ada was supposed to replace JOVIAL. http://www.semdesigns.com/Products/MigrationTools/JOVIAL2C.h...
There are also tools to convert Ada to C/C++/Java: https://www.mapusoft.com/ada-to-c-changer/
I'd start any new embedded system in C or C++ with an appropriate coding standard, static analysis checks, and perhaps run-time ones. No way I would consider Ada. Maybe someday Rust will penetrate more, but it has a ways to go.