Yup… It’s always hard to understand when an UI is more complex than seems necessary. In some cases, there’s just no way to make things magical (e.g., a plane is just a car that goes up and down in addition to left and right, correct? Why so many buttons in the cockpit then? 
).
SmartThings’s less “simple” UI is more likely due to their desire to have a unique look and feel, instead of following any particular design trend. Or they are myopic and didn’t even consider ways to be more simple? They ran drafts of the UI through interview sessions with test users, so …?
I apologize for the shameless plug, but hope it’s relevant: SmartTiles along with SharpTools, SmartRules, etc., were all created with simple elegance being the #1 feature of their designs, even at the expense of not fully replicating all the “features” of the SmartThings native App (the popularity of SmartTiles speaks for itself … thousands of installations).