I know this was several years ago, but people still have short memories. I recall Utah, Boise State and TCU being the G5s that made a lot of racket and were a pain in the ass to many in the P5s at the time. Fast forward a few years and Utah and TCU have had access to P5 money. That difference in revenue probably helped separate them. Had Boise been able to access P5 (now Middle 2) at that time, they would now resemble Utah and TCU.
So the Big 12 schools have a leg up on the new PAC schools because of the revenue difference...at least right now. If Boise, Fresno, SDSU, Colo St, Utah St, are able to get PAC revenue similar to the Big 12 numbers, they'll elevate to the level of those other former G5 schools like Utah, TCU, Cincy, UCF and Houston.
Yeah, the new PAC schools could beat some Big 12 and ACC type schools, but some Big 12 and ACC type schools can also beat B1G/SEC teams. While there may not be a lot of difference football wise in some of these teams right now, over time there is.