[Someone]

I think the group of people who know about and use DSLRs is too small to be the target audience of any of Apple’s smartphones.

Other smartphone manufacturers might be willing to do a product for, at best, a few million users, but Apple thinks focusing on fewer products is the better choice (for them, and, possibly, for all users because Apple can spend more effort on each design)

I would guess Apple’s target audience is everybody who wants to make better photos, whether they know about DSLRs or not.

Yes, they have RAW support, but I think they find that a nice to have, not a must for their product.