The signed form of a language such as Signed Russian (or Signed English, etc.) is usually used in education by hearing teachers. If this situation is considered more prestigious (because of the association with education), then that form of language will get a higher status.

Also, Signed Russian follows – at least to some extent – the grammar of spoken Russian, and spoken languages are still commonly associated with higher status (in the extreme case, a sign language may not even be considered a fully-fledged language).