For the record, I've been on the whataboutism bandwagon for a very long time.
Riots typically occur when people feel powerless. They want to change that state of affairs and believe that force is their only option. But what was the animating force behind the riots you are comparing?
The riots that took place last year began as protests against racial injustice, and devolved into looting and violence. That's a bit of an oversimplification, but the animating force for gathering people was racial injustice, which is a thing. Perhaps Democratic leaders spoke to the message of racial justice, but I don't recall any inciting riots much less condoning violence. By the way, I'm not arguing to the perceived superiority of Democrats. Not in the least. Politicians are calculating, and to incite or condone violence would have been criminal, and possibly prosecuted as such. I'm just trying to establish what differentiates last year from the present.
The animating force behind the mob that stormed the capitol was the belief that the election had been stolen from them. They believe this fiction because the president of the country has told them a massive fraud was perpetrated upon them, despite no evidence of massive fraud that would have changed the outcome of the election. They persist in this belief in spite of the FBI director saying there is no evidence of a massive fraud. And they persist in this false narrative long after several recounts by state officials produced nothing to support their claims, and several dozen lawsuits, including a pair that reached SCOTUS, rejected Trumps arguments. Nevertheless the president spread this falsehood, and told his followers to march on the capitol building.
The difference is glaring.