To be fair from 1986-2011-any non-trade Hal Jordan material (pretty much all Green Lantern material) was limited to comic book stores.
Green Lanterns were MIA in all other media aside from Kyle cameo in Superman Adventures and John in JLA.
For everyone after 1986-John Stewart was the Green Lantern. He was the second black character from DC that most saw not named Cyborg.
New 52 JLA had all the guys minus Cyborg who sold books (something John nor Cyborg got shots at doing). The book was for those within the comic book industry not outside it.
Which was even MORE telling when we saw merchandise of said team and Cyborg was EXCLUDED. Way more than Wonder Woman and Aquaman-who got shafted at times too.
There are JLA party sets-Cyborg nor WW nor Aquaman are there. Hal, Bruce, Clark and Barry are.
Cyborg (along with WW & Aquaman) got shafted on Hot Wheels JLA cars (the first set)
Cyborg got shafted on various Justice League stuff (before movie)
I saw a Justice League binder that had Ollie, Dinah & J'onn on it.
Justice League Valentines that had Catwoman and Batgirl. Not Jim Lee art but Jose Lopez Garcia and George Perez.
So if there was suppose to be a Cyborg push-WHERE WAS IT?
Well the toxic reaction to McDuffie's JLA run (despite it still sold) might be a bigger reason for that. Because management (DAN) actually supported 4 blacks on the team.This is about DC's idiotic "only one black character in the JL" rule, which is clearly still the case to this day even after the former higher-ups have been gone.