I have no issue with trying to find new ways to make similar products. It's definitely interesting in terms of material science and processes. But the options aren't particularly close to anything anyone would actually choose side by side without any of the discussion of ethics. Which, if that's something you care about, whatever. I don't, and won't. That's what a cow is.

But if you have issue with it for whatever reason, there are plenty of perfectly fine and perfectly functional natural options for most things that don't try to pretend to be leather. There are a variety of woven fabrics that work just fine. I'd be willing to bet that you could make some kind of waxed canvas case that's a hell of a lot more durable than the crappy leather Apple uses for a decent bit less money.