Star Trek: Discovery is wrapping things up in its fifth and final season. In doing so, not only are they hoping to tie up every loose end on the show, but maybe one or two lingering plot lines from the wider franchise. The series is hoping to close the loop, or at least further explain the concept of the progenitors in the Star Trek universe.
The idea is that these progenitors are the first beings to inhabit the universe and are the for-fathers of many of the modern alien races we see today, like the Terrans, Vulcans, Klingons, and others. It's a controversial idea as it not only rejects the notion of evolution as we perceive it, but it seemingly embraces controversial doctrines like the Church of Scientology.
The idea of course is older than Discovery and one that was probably on the radar as far back as season one.
Revisiting the progenitor's story could be argued as always being in the cards for the franchise. After all, the writer behind the original episode referencing these mysterious, god-like aliens on The Next Generation was written by Joe Menosky. Menosky not only wrote the episode "The Chase", which introduced the Progenitor aliens, but a host of other great episodes like "Times Arrow", Deep Space Nine's "Rivals", Voyagers' "Scorpion" and Discovery's "Lethe".
He was brought on to Discovery as part of the writer's room in season one, possibly sewing the seeds of this mystery being further explored.
Menosky left Discovery in season, right around when Bryan Fuller did (so far as we can find), but it appears his impact on the writer's room remained. So it's not surprising that the show is wrapping up one of the greatest mysteries that Menosky ever created. Even if he's since left the show.
The show is hoping to further explain away some more things involving these aliens before the final curtain drops, and hopefully what they uncover isn't too outlandish. After all, Star Trek has always done its best to fall in line with accepted scientific facts, so this storyline they're following could have some real disastrous consequences.