There are languages which are more suitable for the construction of high-integrity systems and have been for years. We could have adopted Modula-2 back in the 1980s, people could take the blinkers of prejudice off and look properly at Ada. Yet we continue to use C-derived languages with known weaknesses.
So we trade the known problems for a set of unknown ones? It might be appropriate to do so; C may be "broken" enough that it's better to go for an unknown with a design that allows for a possible correct implementation. I keep thinking of Java, for example. It's a good paper design for security purposes (I'll leave functionality alone for now.) But there are still all the issues with the VM implementation and libraries to deal with.
Language X may very well be a much better starting point, I don't know. I do believe that it will never be properly looked at until the whole world starts using it for everything, though.