Modern Macs use a version of the Unix operating system. It's a version with a lot of Apple-specific "stuff" (like all of the graphical interface stuff) – but like Unix, it's still a multi-user system underneath. That means that you can set up multiple user accounts on your Mac – each with its own login and "home" directory on your disk. Say, one for yourself, another for your wife ,and two more for two kids.
Many people don't do that – they might have just one user account (in addition to the assorted accounts that the operating system maintains internally). But the system still has the capability to support multiple accounts even if you're not using that feature.
Given that background, I think you can interpret "6 items: 2 items affect all users" as follows:
- 6 Adobe Creative Cloud items are running in the background
- 4 of those are running in the background for your user account, only. If other members of your family had their own accounts on your computer, these 4 items would not be running in the background when they were logged in. (For all I know, Creative Cloud could start up a different set of 4 items specifically for them.)
- 2 of them are running in the background in such a way that they affect all users; that they run regardless of who is logged in
My guess is that there is nothing to worry about. But you could contact Adobe Support or post a question on the Adobe forums if you're still concerned.