I don't agree. I think it's confusing because it's the absence of coverage here rather than the existence of coverage, and it points to where we disagree on the analogy.
Software is copyrightable subject matter. Copyleft hacks that.
Racially disparaging logos are not trademarkable subject matter.
That's probably why you're saying it's not a copyleft-like hack, because it's pushing this logo out of subject matter area entirely.
I'd argue it's a different type of hack: finding a part of the legal system that can be used to put pressure on a bad actor and change their behavior in unrelated areas.
Note specifically that they aren't forbidden from using the name or logo now; they just can't do so exclusively. That part is the cute hack: it removes their incentive to be racist, but doesn't change their racism.
GPL removes the incentive to proprietarize, but doesn't cause proprietary software types to stop mistreating users.
That's not correct for a couple of reasons. The registrations for logos without the word "Redskins" were never challenged, so those are the same as always. There were one or two registrations challenged that had the logo, but that's because the registrations also had the word "Redskins" and the team doesn't use those anymore.
Second, and mentioned in my other comment, you are mistaken that the Redskins would no longer have exclusive use. The word "Redskins" is quite likely enforceable nationwide as an unregistered trademark, probably under federal law as well as state law.
The most significant financial effect is that, in theory, once the registrations are actually cancelled (which is still years away) the NFL could no longer have counterfeit goods seized by Customs at the border. But no one imports JUST counterfeit Redskins jerseys, they come in in containers of all the teams' jerseys. So they would be caught up anyway. But I think this ramification from the cancellation of the registrations is the most significant one.