This is the first time the price has changed from $200 in almost a century...
If it had been adjusted for inflation a stamp would be 3k today.
What's likely to happen is now that it's $0 they call into the legality of the registry. Before the rational was that it was necessary to track who paid, because tracking the ownership wasn't legal.
If they're not completely removed, there's nothing stopping it from being changed again later.
I don't see a reason for suppressors to be more regulated than guns, and with "pistol" loopholes SBR regulation doesn't make much sense either.
We need to completely redo our gun laws from the ground up. None of the current system makes sense, but that doesn't mean we get rid of it, just replace it with something that actual works.