Rust does not do prevent all UB statically. Even if you guarantee at compile-time that all execution paths have well-defined semantics because compiler inserted run-time checks, this is not the same thing as "statically ensuring the absence of this run-time condition that would cause UB" which would be what people usually mean with "statically preventing UB". So I think it is not me who uses the works in an unusual way.

If, of course, you redefined words so that adding run-time checks counts as "statically preventing all UB", then this applies to Fil-C just as well! You can not have it both ways.