To whom does any God appear to today?
Franklin's point wasn't about the people of the primitive past seeing God, but rather how when they did they interpreted him. He said specifically, "
To the primitive man of War God appeared to them as a warrior. To the men of philosophy God appeared as Wisdom. To those who sought love between the conflicts, God appeared." The point is about how we interpret our experiences or encounters with God, and his point is an excellent one.
To answer your question to whom does he appear today, everyone really. It's not a question of who does God appear to, but more a matter of who sees God and who does not. God "appears to" me all the time. But it's not a matter of some entity peaking out from behind some cloud and saying "Boo, hey it's me! God!". It's more a matter of pulling back the curtain to see what is there all the time. We are the ones holding that curtain rod. Not God.
I encounter God everyday. I experience God in subtle and profound ways, in the mundane and in brilliant illuminations, in presence and peace, in gentleness and in infinite depth and power. It is only a matter of my receding from this in self-contraction, or allowing in open mind and soul. It is not some entity out there hiding his face from us, but us hiding ours from what is.
Now to Franklin's point, those who have such state experiences will typically then afterward interpret them within the framework of their cultural contexts with their linguistic frameworks (symbol sets), and through their current developmental stage. A child of 8 will interpret an encounter of God as "The clouds smiling upon me". The adult tribal warrior will interpret this as their deity affirming his support of his tribe of "chosen ones". The philosopher poet will likewise interpret God in more universal terms. The mystic sage will interpret God as a force within all that exists. It really becomes a matter of what sort of frameworks allow the experience of the Infinite to fit within. Everyone enters into that awareness, but not everyone subsequently is able to speak of it in the same frameworks of reference. It transcends all frameworks of reference.
So who does today? Same as before. Everyone.