You do not seem to understand that. You made a positive affirmation. You claimed that the gallows were fake. That does put a burden of proof upon you:
"Oh, so it wasn't people with flagpoles, or those breaking windows, or setting up a fake gallows, or getting shot by black cops, or people taking selfies that resulted in the misinformation term "insurrection" being tossed around the past 2 years?
Then Joe Biden must be the one who actually did overthrow democracy by occupying the White House based on the results of the Electoral College"
Now if I claimed that the gallows were real, then I would have a burden of proof. No one claimed that they were real so none of us have a burden of proof. You made one that they were fake. If you asked me if I could prove that a gallows were set up I could prove that. But even you cannot deny that there were gallows there. Could I prove that they were functional? No, that is why I would not make such a foolish claim.