We hate bloatware. Let's stop mincing words. Most everyone hates it, and every time a new phone is released the topic comes up, because the folks making the phones and the carriers selling them all like to put "value-added" applications on the phone before they sell them. Some of these preloaded apps are useful to some of us, but those useful ones can just as easily be downloaded through Google Play by the people who actually want them. Heck, I install the same Yellow Pages app on my phone that AT&T forces on me. It's the forcing we all take issue with.
Recently, folks have been talking about the bloatware on the Galaxy S6 (and, yes, the edge model, too) and how you can't really remove it. While that's an issue of its own — once paid for you own the phone hardware — some are concerned about these apps taking away space for your own applications.
But it doesn't really work that way. We'll explain.
Your phone's storage basically is a hard drive. And hard drives can be partitioned. And once it's sectioned out, you can't change those partitions without wiping out everything on the drive. That's oversimplified, but it's pretty much the same as it has been since we first got disks big enough to partition. We've been doing it on computers for decades. There's a catch, though — repartitioning the storage on smartphone is not as easily done as it is on a computer. (We'll let you all get into master boot records and all that in the comments, if you'd like.)
To understand why deleting bloatware doesn't save space, you have to understand partitions.
The system partition on the Galaxy S6 takes 3.7 gigabytes of the total storage. That's a lot when you're talking 8 GB or 16 GB phones, but not-so-much with a 32 GB or higher phone. (And the GS6 starts at 32GB.) In either case, that's how how much storage the system partition uses, and you can't change that.
On a 32-gigabyte Galaxy S6, the partition where you can install your own apps and their associated data — that's the "data" partition — is 25.2 gigabytes in size. Is that enough? Only you can answer that. You can't do anything to make it bigger though, unless you get really dirty in the OS (with a fully unlocked bootloader, at that), and you risk breaking everything. For our purposes, it's really not something you can change.
There are other partitions and even a bit of unpartitioned space, too. In total you end up with the 32 gigabytes (nominal, not really 32 GB based on 1,024 kilobytes per megabyte) of storage you were promised. All we need to know here is that the system partition is 3.7 gigabytes and the "data" partition space is 25.2 GB in size.
Back to the bloatware. On the Galaxy S6, you'll find apps like Facebook, Google Newsstand, Microsoft's OneDrive, and plenty of other Samsung and carrier apps. Some people will happily use those apps. Others won't. You can disable most of them so that they no longer run and use any processor or RAM resources, but you can't actually delete them and free up the storage space they are using. But that doesn't really matter, because even if you deleted the pre-installed apps you can't use the space they previously occupied.
Deleting (most) of the bloatware on the Galaxy S6 would give you no extra space to install your own apps. This applies for most every other Android phone as well.
Go back a few paragraphs where we talk about the size of the system partition and the data partition. Most of these bloatware apps are in the system partition, protected and considered part of the operating system. Maybe they shouldn't be, but that's a different subject. They are, for all intents and purposes, protected operating system files. If you could remove them (like when you're rooted), they would only free up space on the system partition — a place where you can't install your own apps. Deleting something simply doesn't change the total amount of space used by that partition.
It's still disheartening to see all the bloatware, and there's a good argument to be made that it takes up space. The system partition could be smaller without the bloat in place, making room for a bigger data partition. But the fact that we can't uninstall these apps makes little to no difference in the amount of space for our own apps.