But there's very little historical data to look at. Only a few non-P5 one-loss teams in the CFP era. In reviewing the history, however, it's clear that SEC membership allows for 2 extra losses, compared to a non-P5 and allows for 1 extra loss, compared to other P5s. Undefeated G5s, like UCF, is on par with a 2-loss SEC team, or 1-loss other P5.
Pollsters and committee members have definitely settled into a rhythm where one-loss SEC teams always get ranked higher than all other one-loss teams. Same for two-loss teams, etc.