> To apply your logically consistently, you'd also have to throw out Go[1], Java[2], C#[3], and plenty of other languages

Yes? Is Fil-C not obviously safer than those?

> I guess you can define a logically consistent taxonomy of languages where Fil-C is the only "safe" language any everything else is unsafe, but then the burden is on you to prove that it's a useful way of thinking about them. Meanwhile, the way that people who consider Go and Java and Rust to be safe and C/C++ to be unsafe will continue to see actual real-world differences in outcomes when using a safe language compared to unsafe ones.

It seems like "can switch on unsafe whenever" vs "has no escape hatches" is an obvious line in the sand and a very useful distinction with real world implications.

> Maybe Fil-C will be able to provide as large benefits to running C safely in production like its proponents claim in the future

Why in the future? It exists and can be used right now. In fact, much of its appeal is being able to use existing code without needing to port to a new language; pragmatism seems like an argument in its favor.