The TNG films came out in an era where there was far more studio interference than there were with the TOS films. There simply were too many cooks stirring the pot!
Seriously, instead of making -- for the lack of a better word -- "quality films" in their own right, the TNG film franchise tried to compete with other films that had nothing to do with its own genre. Picard aping Die Hard
in the films being one of the prime examples.
Just imagine TMP with a whole laundry list of things to include from TOS like it was done with GEN; TSFS being re-written to the point where it didn't make much logical sense like INS; TUC being helmed by a non-director with a hack-script and choppy editting all over the place...