Congress only cares about those victims of riots least deserving of sympathy: themselves.
Aside from the obvious ideological motivations this is another factor for the difference in reaction despite the summer 2020 riots having a considerably higher degree of violence. The 2020 violence wasn't happening in parts of towns where members of Congress live so it didn't directly impact them.
And of course just because it can't be said enough; the majority of people harmed or worse during the 2020 BLM protests were protestors attacked by police or by violent alt-right counter-protestors.
Is this counting or not counting the many victims, direct or indirect, of property damage?