If it was shut down ... then exactly what would the perps have been nailed on? It would errh MIGHT have shut down the narrative - but that continues even to this day & tomorrow - and it’s presumed, for purposes of these discussions, that Hussein pre-emptively pardoned all of his folks - so you had to nail them on their activities after Trump became POTUS. These things take time unfortunately to wrap everything up in a way that can be prosecuted.
Perhaps it is post-surgical fog but I don't see how appointing another Democrap as Chairman of the committee changes anything - except Schiff using the authority of his position to rip national unity to shreds. Presumably Schiff's successor would be more circumspect. Schiff is possibly a psychopath IMO. {A graduate of the Alec Baldwin School of Human Relations.}