TNT has dreamed his whole life of BYU joining a P5 conference. Fantasized about what it would be like.
After decades of not seeing that dream come to fruition he has come to the opinion that P5 membership would only enhance BYU's football operations "a little bit." The reason is this. BYU takes pride on not letting athletics run the show. Ultimately recruiting would improve somewhat (ceiling of the Honor Code of course) but football wouldn't all of a sudden change its stripes. Many of these schools are absolutely desperate for the money they get from football. BYU is not in this position, and for good or bad in regards to football status, is unique in this manner.
What he is anticipating would happen is that a lot of other projects around the university would be able to be funded. So if you would be excited to see the university expand and grow in other ways P5 membership would be great. But if you were hoping BYU would elevate to a consistent top 30 program in facilities and the like you would be disappointed. But it would provide most likely long term security for the program.
Just a poor guy's opinion.