> We got to this stage of having to sync because Apple can’t stand putting more storage on client devices.

It's not why I use sync services. All my photos fit on my devices (more or less). But I want to have seamless access to my files from both of my devices. And most importantly the sync is my first line of backup, i.e. if my phone gets obliterated I don't loose a day or two of files and photos, I only loose a couple of minutes.