>>1 It can be harder for anime companies to get good story writers on board, while it's far more easier just to pick up like the top 50 or 100 most popular manga and turn that into an anime.
"Darling in the Franxx" somewhat makes me think of "Chrome Shelled Regios" as both anime have large domed cities that move on tracks, but the clear difference is "Chrome Shelled Regios" is not a "mecha" anime, strangely enough "God eater" made me think of it as well because of the large lifeforms in "Chrome Shelled Regios".