What exactly is the Big 10 style vs. the Pac 12 style? If you're thinking the Westerners are used to finesse and a "gentler" style of basketball, you're gonna be surprised. That line of thinking is outdated by a decade or so.
I thought he was talking about the ref style, and they are different. My favorite theme, but we came from the old Big East in 2011 out west to Arizona. The difference was shocking. We were out here before the oBE broke up into the American and the current Big East, and before Rutgers went to the B1G.
In my experience, again back then, the Big East officials (many of whom are still around and in the B1G among other conferences) were more likely to call fouls on "scrums" and more likely to make calls on physical play under the basket. To me, where fouls are concerned, the PAC is the conference of calling the touch fouls. Or as my wife likes to say - beat them up but don't dare touch their shooting arm. And this was fundamentally different.
That said, I don't think the majority of PAC refs that don't already work some eastern conferences (and there are a few that do) are suddenly going to join the B1G staff. Some, but it is very unlikely that you are going to have any referees that do 100% of their work at the former PAC schools. And many of these referees are used to less travel than is common among the eastern conferences already.