I don't think it affects BYU one way or another, other than maybe weakening the WCC a bit by removing a good coach who is helping strengthen the middle tier of the conference. I think Lorenzo Romar and Damon Stoudamire are both short-list candidates for the Arizona job.
Romar spent over a decade in the P12 and had some success early in career at Washington. He's generally done a good job at Pepperdine. Plus he was an assistant at Arizona for a year after getting fired at Washington before taking over at Pepperdine.
Damon Stoudamire is an Arizona alumni who took a bad Pacific team and turned them into a 20 game winner last year, winning the WCC coach of the year. His work plus his popularity with boosters make him a fairly strong candidate.