Geography, TV Ratings, on-field results etc. Those are all going to be much more important, because those are the things that drive money and success (which drives money). And we have (mostly) good answers to those questions but so it's the height of naivete or homerism to believe other schools don't likewise have strong answers to those questions
If we can sell ourselves as the best from a $ perspective, Sunday play is a minor adjustment and not a huge deal. If we can't? Then it provides a convenient excuse for every party involved. Big 12 isn't going to talk about their criteria anyway except to publicly laud those who they do invite. Writers have an interesting point to focus on because BYU is unique in that regard. And BYU fans can put the blame there instead of on other factors (which might hurt more to admit to ourselves).