From The Truth About Guns:

As the Biden administration gears up to pass fresh guidance on pistol stabilizing braces, I humbly suggest that this is precisely the time to get working on legislation to remove SBRs — short barreled rifles — from the purview of the 1934 National Firearms Act.

Arguments and assertions from the DOJ / ATF / Biden administration related to pistol braces only strengthen the case that SBRs shouldn’t be subject to special scrutiny as compared to rifles with 16-inch or longer barrels.