Consider the source. Its Adacore, the support open source Ada. I know them from the Ada on x86 seminar they held at my employer (we were using Ada on PA-RISC). Nice people but pro Ada (or its "Spark" language which I guess is like Ada).
But another huge issue is that C is the language used by the OS. If you want to use that OS functionality to allocate memory, do networking, IPC etc, you are using a C header file and calling into it. We had a binding library to making calling C from Ada easier, but its still an extra step. The good news is that other languages are starting to have some great libraries.
Ada and Rust and a bunch of other languages are safer than C, and likely a better choice. Its just there is a lot of existing code to port over.
But another huge issue is that C is the language used by the OS. If you want to use that OS functionality to allocate memory, do networking, IPC etc, you are using a C header file and calling into it. We had a binding library to making calling C from Ada easier, but its still an extra step. The good news is that other languages are starting to have some great libraries.
Ada and Rust and a bunch of other languages are safer than C, and likely a better choice. Its just there is a lot of existing code to port over.