Streaming is more for convenience. If you want everything, you aren't saving money streaming vs. cable, as the multiple subscriptions add up.
Other problems with streaming on Apple right now.........
Apple only has an app available if you have an I Phone. If you have Samsung, there is no app available to pull up Apple TV. Rather, you have to go into your web browser and type in the website and log in that way. It's not quick or convenient.
Most of us "channel flip" when watching games - whether they be on traditional cable or online such as YouTube TV. It's super easy to switch to another game, if only to see the score or if something exciting is happening. With Apple, your only option to watch is going to be the PAC-12. You have to deliberately seek it out. So not only do you have to buy a subscription to Apple, you have to sign into Apple and actively seek out the PAC-12 game. You can't simply change the channel. You have to actively seek it out. No way the casual fan is doing that. Out of sight, out of mind.
Look at how much the ratings for NFL Thursday Night games went down when it moved to streaming..........and that was on Amazon which has MILLIONS of subscribers over Apple.
Look at MLS on Apple. By all indications, the numbers are much lower than anticipated. The PAC-12 cannot afford to have much lower than anticipated numbers. They have budgets they need to project out that will depend on an exact revenue forecast, not an anticipated one.