one of the reasons Ada lost to C++ is that C++ was not standardized, every compiler was a little different, but there was a C++ compiler available everywhere, and cheaply.
Ada on the other hand had very strict certification requirements for compilers, as such making a compiler that could be called Ada was more difficult and expensive, and then you had to pay to get it certified.
this delay in availability and increased cost hurt it's availability for casual use, you would only have an Ada compiler available if the decision was already made to use Ada for the project