[pjmlp]

Ada never caught on for several reasons:

The compilers were priced in values totally out of reach for most mortals, which ended up buying Modula-2 or Pascal compilers instead.

On UNIX systems, it meant buying an additional compiler beyond the C one that was already on the box. When UNIX SDKs became commercial, you had to buy two (UNIX SDK + Ada), which was even less appealing.

C++ was still coming into the world, and most compiler vendors though that Ada was impossible to be fully implementable and thus never bothered. Ironically, Ada compilers are much simpler than C++ ones.

Finally nowadays from around 6 surviving compiler vendors, only GNAT is community friendly (in spite of the usual license discussions), the remaining ones keep selling their compilers at enterprise prices (talk first with the sales team way).

So it is hard to get mass adoption this way.