Consider another possibility: Many of the J6'ers were guilty of nothing more than trespassing (after entering an open area with no posted signs saying it was off limits). Justice is supposed to be blind, but in this case, some J6 protestors were subjected to what amounts to cruel and unusual punishment, and torture.
I peripherally knew some people who went. They weren't criminals, and weren't interested in overthrowing the US government. They were going because they had concerns about the integrity of the 2020 election. I didn't know them well enough to find out whether or not they were arrested or prosecuted, but it's likely that some were.
So for these first-time offenders, who walked through the open doors of the capitol who spent months or years in prison awaiting trial, and lost their homes, jobs, and more, and who have now been pardoned, the fund will provide some compensation for the weaponization of the DOJ against them.
Other more serious "attacks" on the Capitol that also resulted in presidential pardons: (Google AI lied, and corrected itself when I called it out. Where is this training data coming from?)