I blame Republicans too. We had a majority right after Trump got in, and a Hearing Protection Act ready to go, IIRC, before any "mass shootings" that year. Had it been pushed through right away, I have little doubt Trump would have signed it. After Las Vegas though, I agree with you that it's remote that it will be passed even with a two house majority next year, because suppressors are now negotiation chips.
And with that, I might have just talked myself into a third suppressor to send to jail ASAP.