I think what is obvious now wasn’t obvious then. If you think about how Linux and the open source community rallied around C, this was at complete odds to what was being taught at a university level. It’s a miracle C survived (if I only through new C++ programmers thoroughly rejecting its promise and sticking to “safe C++”). Even still, rust is a solution to memory lifetime problems with a modern toolset, it’s not solving ergonomic problems which is how you attract new developers. Similarly, ADA was a better language, probably pascal too, they didn’t win.