I've read that SpaceX uses C++. I'm surprised safety critical systems like SpaceX and Tesla don't use Ada. It's a mature safe language used in their industry, yet they choose C++.
I don't have any experience on this field, but researching the subject some time ago I found that C/C++ is not unusual too. On the safety matter, when used in critical mission systems they usually follow a guideline or framework to ensure the reliability of the software, like MISRA C[0] for exemple. Another important point is that the development is real slow compared to other segments of software engineering and often takes several years to develop, with lots of tests and rigorous compliance with specifications.
Its an interesting field, but feels hard to get into.
I've seen a lot of Ada code in aerospace projects, but the trend for 15+ years seems to be to write new projects in something else (usually C or C++), and sometimes even rewrite old Ada software.
In this industry, knowing Ada could still be useful, even if only to read it.