There's a plan to make the G5 conferences as meaningless as FCS.
If the G5 conferences have their own playoff, that means the highest ranked G5 conference champion no longer gets a bid to a New Day Bowl, since they'll be playing in the G5 playoff instead. So this year, Western Michigan wouldn't have to opportunity to play Wisconsin in the Cotton Bowl. They'd also have to give up the other bowl games if top teams are in a playoff instead. So the G5 teams would be giving up their share of the CFP and bowl money, and they'll be giving up their share of the potential exposure which is probably important for players, coaches. That will make recruiting harder, and will start a vicious cycle where recruiting declines, quality of play declines, and fan support declines.
Sounds like a lose-lose situation to me. At that point, the G5 teams should just decide that they want to drop down to lower-cost FCS, or form a separate lower-cost division between FCS and FBS.