(We didn't talk about iPhone, so either it had not been announced yet, or development was still so closed down, that it never came up as a topic of consideration.)
My recollection was with their ZFS work, while it was clear to everybody that Time Machine should be a big benefactor of ZFS, they were still unhappy with the high RAM requirements (and also not thrilled about the high CPU requirements). Since laptops were then the bulk of their sales, and these machines shipped with much more constrained specs, there was a lot of uncertainty about when/if they were going to make ZFS the default file system.
(Looking it up, the base 2006 Macbook had 512 MB of RAM, and shared RAM with the Intel GMA 950 GPU.)
I recall there always was a secondary backdrop of concerns with the ZFS license and also the fate of Sun, but the engineers I spoke with weren't involved in those parts of the decision making process.
From one of the co-creators of ZFS:
> Apple can currently just take the ZFS CDDL code and incorporate it
> (like they did with DTrace), but it may be that they wanted a "private
> license" from Sun (with appropriate technical support and
> indemnification), and the two entities couldn't come to mutually
> agreeable terms.
I cannot disclose details, but that is the essence of it.
* https://web.archive.org/web/20121221111757/http://mail.opens...* https://arstechnica.com/gadgets/2009/10/apple-abandons-zfs-o...
What the lawyers say is different.
What the business folks who control the license say was very different. FUD and an unforeseen lawsuit hanging over your head at some random point in the future when Sun or Oracle needs a revenue lift at an end of a quarter is a recipe for ulcers.
Bonwick was the Sun Storage CTO and after the acquisition a vice president at Oracle.
https://www.theregister.com/2010/09/09/oracle_netapp_zfs_dis...