Federally, no. If anything, 41F made them harder to get (and no "pro gun" administration revoked that ruling, hmmm) but I'll say a few states have. No, not the Make-Your-Own laws, but until a few years ago Kansas (where I live) banned all NFA devices. Now I can get SBRs and suppressors. So, I do. A few others have also done so.
And... I dunno. Not sure why they took off, but they just did. Maybe the wars, seriously. Lots more call for suppressors so more people making them and coming back from even reasonably specialist unit deployments knowing that's the next thing, so more companies started up than the few that have been around a long time.
A few more might have popped up because of the push for the HPA, and the belief that we'd get them removed from the NFA. That never went anywhere but MAY have given some more boost to the manufacturing side at least, to start companies, and push them.
But overall, not sure what drove it. Happy it did. Easy to buy, not that expensive, really neat. Makes shooting (rifles) much more pleasant.