The bug there is implicitly converting an r-value to a non owning reference. We wouldn't call the same semantics a bug with a 'char const*' to be fair. We would

The bug there is implicitly converting an r-value to a non owning reference. We wouldn't call the same semantics a bug with a 'char const*' to be fair. We would complain that string implicitly converts or reject the application code as buggy. That being said, yes, string semantics are hard. Passing around copies of a string buffer (std::string) or calling to_string_view everywhere don't seem better.