producers are not wedded to ST movies for very long, and really just don't care.
QFT, and that explains more trek than the terrabytes of fan produced nonsense rationalizing producer apathy ever will.
Oh and the original studio model for the d7 didnt have a gaping hole, just shadowing caused that. Whatever is in there looks deflectorish to me.
Studio model of the green D7, the Groth, has no hole at all in the bow, maybe they cgi'd it in.