A Star Trek cultural POD:
Michael Piller's "audition" freelance script for The Next Generation doesn't include a scene with a conversation built around an extended baseball metaphor. Piller credited that scene as what got Rick Berman to fall in love with an otherwise unmemorable script, as Berman was a big baseball fan. As a result Piller isn't hired, and doesn't take over the show's writing staff.
Piller, unusually for an early TNG writer, was a big advocate for "Roddenberry's Box." Gene Roddenberry's driving concept for TNG said that humans in the 24th Century were more evolved: they didn't have conflict with one another, they didn't grieve for the dead, and they were all-around perfect people. TNG's original writing staff hated the Box, and many of them left at the end of Season 3 when their contracts expired. Piller, as he rebuilt the writing staff, bought freelance scripts and hired new writers who could work inside that Box. He thought that the challenge it presented helped to develop better Star Trek stories.
Without Piller, whoever ATL is in his OTL job could take the whole franchise in a very different direction. If ST:TNG loosened up its dramatic rules, then many of the reactions to it within the genre will be different. (The nuBSG being the most extreme backlash against the "perfect people" concept.)
Speaking of nuBSG, Ronald D. Moore could very well not get his first freelance script picked up. Piller was the one who picked it out of the slush pile, and, after Gene Roddenberry deep-sixed it for not conforming to the Box, personally reworked the premise to satisfy Gene. Piller's ATL replacement could easily not pick up the script, or could drop the matter due to not being able to come up with a workaround for the Box. Without his script being picked up by the show of his dreams, Moore would shortly enlist in the Navy as he had planned.