Error with all Wizard subclass Savant features (has been for over a year)

The (Divination/Abjuration/Illusion/Evocation) Savant features are adding the chosen spell as "Always Prepared" instead of just adding it to the spellbook. Since wizards can arbitrarily add or remove any number of spells to their spellbook, the feature probably doesn't need the interaction boxes to select spells at all. 

Completely agree! Especially since the savant feature only provides two selection boxes, with no additional boxes despite the intent being to grant free bonus spells each time a new spell slot tier unlocks.

It's inappropriate for the feature to have dropdowns at all. Just add the spells to your spellbook. In that sense, by ignoring the dropdowns, the feature can be used normally.