Yes, multiple methods of noise reduction and gating
I've watched an engineer spend many hours obsessing over three minutes of product.
Professional work is not setting levels and rolling.
Although hiss isn't truly terrible when it passes through tubes.
Listen to Allman Bros. Ludlow Garage, sound is fine, hisses like a lawn sprinkler
Most of all it is genuine.
That hiss was in the air that night, PA had it, amp stacks had it, brains buzzed it, etc.