There’s a lot of small QOL features across the system and changes to the UI that depending on your taste, either like or dislike. For folding devices, it adds a huge ton of enhancements too that Google hasn’t bothered to add. I personally can’t go back to stock Android because of how lacking it is by comparison. Stuff like:

• An older style notification shade where you don’t have oversized setting toggles
• Built in sync with Windows for notifications, copy and paste, file system mounting over Wi-Fi
• Customizable lock screen, notification shade, volume bar, “navigation gestures”, task switcher
• Built in support for half open folding states for numerous stock apps with additional utilities for apps that don’t support them
• Override app aspect ratios for apps on folding devices
• Samsung Pay which works a whole lot better than whatever Google keeps renaming GPay into
• Allows any app to become a free form floating window before Android 15
• Allowing me to get away from how personally hideous Material U looks
• Built-in “Tasker-like” feature

There’s a lot more stuff here and there but these are just things off the top of my head.

It’s a strategy to give all Samsung products a distinct UI that has common elements across all the different things they make.

It’s all about having “a look” and making it slightly harder to pick a different option. Apple strategy.

I use Samsung phones for work, it’s really just some UI changes, and they’re genuinely much worse than just stock android. Samsung is just trying to differentiate itself.