It wouldn’t be conceding. It would compromising but don’t even worry about it. Bump stocks will end up banned anyways and we won’t get one effing thing out of it as usual.
It's the very definition of a "concession" -- exchanging USA-WIDE-CCW for bump stock banning.
Although I have no intention of ever buying a bump stock, because I think they waste ammo and trade accuracy and reliability for rate of fire. Nevertheless, they should not be banned -- this encourages the Federal Leviathon to act outside its Constitutional box.
To avoid legislation manufacturers and distributors will stop production and/or limit or stop distribution. However, the GOPe may try to convince the BATFE to change their regulations. And the only way to do that is to redefine what "full-auto" means. Redefinition is probably even a more dangerous slippery slope.
Don't feed the crocs.