Apple is a trillion dollar company, not because they produce inexpensive products.
Apple is a "trillion dollar company" because they are last quarter's winners of the Wall Street popularity contest... and while that "trillion dollars" can be leveraged in various ways, no significant portion of it can ever be cashed in - its not a gold-filled swimming pool*, If Apple don't keep turning in impressive looking growth quarter after quarter, that trillion could rapidly vanish - and the markets won't care about sustainability because they know how to make money off a
falling share price, too. It's very, very dangerous to assume that because you're Wall Street's darling today then you must be doing everything right.
So if Apple's results in the last year came from hiking prices rather than finding new business, they have a long-term problem - because its not far along that path before your product becomes a niche status symbol for millionaires. If you make designer handbags then it doesn't matter whether you sell 1000 units at $1,000 each or 100 units at $10,000 because handbags don't need a third-party software/support ecosystem - if you're the only one at the Ambassador's ball with an Apple handbag, that's perfect - if you're the only one at the conference with a Mac that could start to be a problem.
I'm sure that Apple (the brand) could survive by selling $10,000 MS Surface clones encrusted in Swazwhatnot crystals, but I think most people here would have lost interest by that stage. However, they'd probably still be advised to do some $100 T-shirts or rose-gold styluses that little people could afford in order to maintain the brand image.
Meanwhile, low-cost machines make money, too. Part of the original plan of the "Mac Mini" back in the day was to produce a low "sticker shock" item that would at least get people in the door (either literally, at an Apple Store, or figuratively) so you could up-sell them. The reason
I'm currently using a Mac as my main machine rather than a PC is that back in 2005-ish I got a Mac Mini to "play with" - and upgraded to a Mac Pro six months later (well, the fact that I like Unix also contributed - but that's probably not such a big seller).
I don't see Apple ever producing a $400 laptop or Mini to compete with commodity PCs and Chromebooks (you need
some margin if you're going to roll your own OS) but I think it would be a huge mistake if they didn't keep a credible sub-$1000 offering (...and then its the job of Apple staff to make sure that a fair proportion of customers who walk in the door for a $900 Air walk out with a $2000 Pro).
(* although Apple have one of those as well, but that will just make them a juicy asset-stripping target if their shares have a bad hair day...)