The article gives another reason "A second answer is aesthetic. Ada's syntax is verbose in a way that programmers with a background in C find unpleasant. if X then Y; end if; instead of if (x) { y; }. procedure Sort (A : in out Array_Type) instead of void sort(int* a)."

I think this should not be underestimated. There is a huge number of small C compilers. People write their own C compiler because they want to have one.

That doesn't happen we Ada. Very few people liked Ada enough that they would write a compiler for a subset of the language. For example, an Ada subset similar to the feature set of Modula-2 should be quite doable with a modest effort.