They depend on at least 50% of voters to have the short term memory capacity of a baby hamster.
They'll show 5 times daily the clip of Hidin' Biden from 2 days ago forcefully denouncing the riots, while "reminding" us that Biden denounced them from the very earliest moment, while Trump did & said nothing because he hoped to pin the blame on Democrats to help his re-election.
They'll get at least SOME extra votes from low-memory capacity voters, but hopefully not a lot. Mostly what they'll do is give more talking points to partisans who are willing to believe 10 mutually contradictory lies about Trump simultaneously in order to feed their hatred of him.
Hopefully the low IQ voters can't find their polling places.