The only way a bill is truly killed is if it is defeated in floor vote. There's a long way before a bill reaches that point- most never do. Feinstein has been introducing garbage gun control bills every year like clockwork. They never make it out of committee, let alone to a floor vote. I only really start worrying when a bill gets approved by committee. However, if the leadership of that house of Congress sees no chance of passage it won't make it that far. That goes double for a bill that is sure to lose people votes (as gun control tends to do).
I will not be surprised if there's some kind of change to a background check bill, and quite honestly, I don't know that one is all that loathsome. I know why it is not a cure for anything, but it is not near as bad as an actual federal ban. I'm waiting until something starts to get through committee before getting concerned, let alone worried.