Rename and generalize the rule "Input Fields cannot reference inaccessible type"?

[glen-84]

For a rule like Input Fields cannot reference inaccessible type, since the type won't be inaccessible in the composed schema, but rather "missing", will the rule be renamed to something like Input Fields cannot reference missing type, and the algorithm changed to just ensure that the type referenced by an input field exists? (a shorter name/error code would also be nice)

Also, could this rule be generalized to any field that references a missing type? It's not limited to input fields, is it?