Correct. Even before there was an incentive to keep a G5 team out of the top-8; being undefeated was unlikely to be enough, given the number of games in that conference schedule. An undefeated Big XII team is probably ok in a straight-8 format.
2014: #20 Boise (11-2)
2015: #18 Houston (12-1)
2016: #15 Western Michigan (13-0)
2017: #12 UCF (12-0)
2018: #8 UCF (12-0)
2019: #17 Memphis (12-1)
2020: #8 Cincinnati (9-0) -- COVID season
So the G8 can figure they have a shot at the playoff, as the bottom seed; so long as their is a global pandemic or if they have completed their second-straight undefeated season... because those are the only times they've been close.
Again though, that was before there was an incentive to keep G5 schools from being ranked #8... I'm willing to bet Cincy ends up #9 if a straight top-8 would've reached the playoff last year (they were already behind three loss Florida); so yeah if you can go undefeated for two straight seasons, then you might, just might have a chance to be the bottom seed out of the G5 in a straight eight format.