This is mostly just silly. They generally, historically, have released almost no products with retina at all. They've barely been using it for a year and have integrated it into just 4 products now across their entire catalog, zero of which went retina on their second generation.
I also don't think they're withholding retina or cpus from anything so they can introduce that feature in coming years, this technology is moving crazy fast, it's already expected in higher end phones and tablets and after that it becomes normal.
Cost is the only reason they'd withhold anything, they target a market and what that market can pay and then they cram as much as they can into that price without sacrificing their enormous margins.
I also don't think they're withholding retina or cpus from anything so they can introduce that feature in coming years, this technology is moving crazy fast, it's already expected in higher end phones and tablets and after that it becomes normal.
Cost is the only reason they'd withhold anything, they target a market and what that market can pay and then they cram as much as they can into that price without sacrificing their enormous margins.