There really is no political gain by passing the HPA. There's just no juice behind it for the average voter. Congressmen like mine get credit for co-sponsoring the bill and he can sit back while it dies in committee. Trump can get credit for saying he would sign it but the bill never hit his...
The product is your's the minute you pay for it.
The government holds up the process. You can't just apply for a silencer. You have to apply for the silencer you bought with product specifications and serial number. The dealers have no control over when the ATF gets around to mailing stamps.
I have my doubts about the HPA passing but The BATFE could streamline the process. The FFL could file the paperwork, run a NICS check, collect $200, and hand over the silencer. At the worst, a buyer could get stuck with a 72 hour hold.