Barr has the authority to declass. He wasn't handed a pile of declassified stuff. Though you're still correct - just because something is not classified doesn't mean it will be released to the public.
I think he kinda was. And recall that he went to certain heads of agencies with it to consult on releasing it.
Though you're right. Probly not 'piles' of stuff, as in paper files, though maybe. Much is probably digital with secret passwords and stuff like in the movies. High tech and whatnot.
Hannity asked POTUS in his interview last night when he was going to declas. POTUS said he gave Barr the authority to release...maybe to Devin Nunes... and then he said 'so really, I have already' (declassed).
Draw your own conclusions. POTUS also had a very weird tone in his voice when he said 'maybe to Devin Nunes'. Tone's not the right word maybe it was just a special inflection.
Things are gonna get interesting.