It is if you start blocking but if you are just running your route I don’t think it is a pick. They used motion and sort of a rub route on that play so I can see how you might think it is a pick. I think it also needs to be downfield so 5 yards past the line of scrimmage. If the ball is the in air I believe offensive players can begin blocking.
In the PAC12 who knows. Cal could do it all day long last season and Utah does it once and gets flagged. I really don’t think refs know the rule or how to identify it because so many things are happening on every single play. I haven’t seen too many offensive PI’s called this season despite it occurring quite a bit.