This argument can (and should) be applied to TFA (and most works of fiction).
It wasn’t necessary to advance the plot though. Any story can have superfluous touches for added effect, and that’s OK. One or two little coincidences are acceptable, because hey, life is full of them.
When the plot cannot advance though without coincidence A, and then coincidence B, and then coincidence C, and then coincidence #57 … the audience gets the feeling they are no longer watching a believable story, but rather a string of poorly written contrived coincidences.