i can go on all day about this, but this comment has summarised it nicely, you have to understand that to be compliant with DO-178b/c you need to do an un-godly

i can go on all day about this, but this comment has summarised it nicely, you have to understand that to be compliant with DO-178b/c you need to do an un-godly amount of v&v and other things that literally cost millions $ per quarter in a span of a single project, c is much easier to prove right and can easily achieve a good test coverage, c++ on the otherhand is considered a "high level language" and is used for instrument panels and such things, down the stack however you will see people using much more conservative languages.