So, here's the thing.
For the most part, the Angels haven't really developed a lot of star players through the draft. They don't have a real history of developing talented players. The one's they have developed, they've been able to retain (for the most part) when they hit free agency. Mike Trout is the classic example. They also retained Jered Weaver, Tim Salmon, Garret Anderson, Chuck Finley, Howie Kendrick, and Darin Erstad.
One guy (of somewhat recent times) who left when he became a FA for the first time is Troy Glaus, but Glaus hadn't been productive in his last season in Anaheim due to injuries. Wally Joyner is another guy who left via free agency when he had the opportunity.
Maybe there are others, but I can't think of them off the top of my head.
We've been kind of lucky. The Angels have; for the most part, been able to retain "their own" stars while they were in the prime of their careers. Granted, they haven't developed a lot of those, but you get the point.
Even thought Ohtani wasn't drafted, he's someone who began his MLB career as an Angel. We're in rare territory now. We are faced with the possibility of losing one of "our own" via free agency while they're still in the prime of their career.
We're not the A's. We're not used to dealing with these scenarios.
Throw in the fact that Ohtani is a once in a generation talent and it makes all of this extra hard.
If Ohtani leaves, I'm not sure how I'll react. I'll be disappointed for sure, but it's just not something I want to think about. I hope he stays. I hope he stays for all the right AND wrong reasons. He's just one of those guys I really don't want to see in another uniform.
I'm glad I never had to see Salmon wear another uniform. I'm glad I won't have to see Trout wear another uniform. And even though I hated seeing Weaver and Anderson and others in different uniforms, it was understandable - given where they were in their careers.
If Ohtani leaves it will just suck. There's no other way to look at it.