I don't think runtime error handling is impossible in Fil-C, at least in theory. But the use cases for that are fairly limited. Most errors like this are not anticipated, and if you did encounter them then there's little or nothing you can do useful in response. Furthermore, runtime handling to continue means code changes, thus coupling to the runtime environment. All of these things are bad. It is usually acceptable to fail fast and restart, or at least report the error.
I could have made Fil-C’s panic be a C++ exception if I had thought that it was a good idea. And then you could catch it if that’s what tickled your pickle
I just don’t like that design. It’s a matter of taste