Yes, P2, P5, G5 are technically just nomenclature, but you understood the intended meaning behind the term, didn't you.
Now I'm not at all familiar with the other playoffs and divisions that you talk of, but is there a chance that there is more "even-ness" across the entire leagues?
Just because every other sport does a playoff that way doesn't mean major college football should change - that's just your opinion. It's not right, it's not wrong, it's your opinion. But why give up the one thing that makes you unique? No G5 team will ever win a national championship, so why waste everyone's time? Or are you naive enough to think otherwise?
Final question - how would people have felt if Cincy took out Bryce Young in that game, or if Oklahoma took out Joe Burrow in 2019 even though Oklahoma didn't belong on the same field as LSU?