I don't know if 5e changed it but smite is a paladin spell attack. Like magic missile for wiz.
did they auto basic attacks? Let me know when they auto basic attacks so I can watch you people complain about something else.
So in this scenario you want to compare a basic spell attack to reaction skills / spells. An why you can choose basic actions while you can not choose when to do a reaction. Why do you think Larian did it this way? Why do you think any game would do it this way? My answer would be still the same from previous posts, scroll up and reread them.