[Cyph0n]

As someone who works on a significant C codebase (IOS-XR), my 2 cents:

1. Most of the large userspace C codebases that still exist today didn’t have many alternatives when they were started.

2. Any non-trivial C codebase relies much more on runtime testing than other languages. In other words, with other languages, you can get away with fewer tests while achieving the same level of quality.

Note that you should be striving for comprehensive tests regardless of language; this is just an observation.