Grassley is putting this out there to help lay cover for Barr. Traditionally, the FBI/DOJ are supposed to stay out of elections–that's a big part of why there was so much uproar when Comey piped up about HRC in late 2016.
If people start insisting that Barr release details, it would be better for him than if he just suddenly did it on his own. So we should all be doing the same thing–demand that details be released -before- the election.
I'd expect others to be chiming in as well soon–like Hannity and others on /ourside.