I guess we're disagreeing about the semantics of "C but better" then. Your position seems to be that a contender would need to be able to replace (and improve)

I guess we're disagreeing about the semantics of "C but better" then. Your position seems to be that a contender would need to be able to replace (and improve) C generally, and I don't totally agree (not that you need to be convinced, but I'll elaborate on my interpretation anyway). E.g., if somebody came along and said that C would be bloody perfect if it just had a garbage collector then that alternative language would be totally unsuitable as a replacement for C in many contexts, but for a ton of other scenarios it'd still be "C but better," and I don't know that it should be disqualified just because it isn't a full replacement.