I hear ya... but for a non-cleric/druid this is pure fluff. Sure... if they have time to, add a place where you can select this, but there is no significant distinction between a player saying to themselves "This is the god my character worships", and having a "God worshipped" slot on the character sheet.
I would rather see Larian put their time and effort towards getting that full release out sooner than later.
Also anybody with the Acolyte background. The Acolyte is a de facto priest regardless of class. This isn't particularly new either, non-cleric and even non-caster priests go back all the way to 2nd edition and probably further.