2dognight You are correct. Google Camera and some other apps that only did a check to see if GSF is there now no longer needs it at all.
Of course, Sandboxed Google Play enables more functionality for Google Camera like the AR stuff, but the base functionality that previously required GSF (not necessarily Play Store or Services), now doesn't need GSF at all.
You can use Aurora Store to obtain Google Camera, as an example. Aurora Store is a Play Store frontend that sports disposable accounts, making it so you don't have to create your own to use it. It's not without its issues, but it's an option for people who don't want Sandboxed Google Play in a specific profile (or at all).