There's no contradiction there, despite your efforts to portray one.

People often take glee in and celebrate violence even as they commit it against others.

The german language has even given us a word for it: schadenfreude.

Thanks to the lies from the politicians and media personalities they follow, primarily the president, many of these people also fantastically believed that they were overturning a fraudulent election, and were therefore celebrating what they thought was an imminent success in that objective.