Continue with the previous config. If the config-loading function was fallible, and that bubbled up somewhere, someone might say, "Oh this can fail, we should do blue-green for configs the same as we do for exes." With it being infallible and a panic, that gets hidden.

If I was designing a language to surpass Rust, I'd make panics opt-in. I think Rust has a team looking into no-panic but it's a funny loophole for a language that wanted to eliminate crashes.