"If so, please look it up and provide citations."
"Saying "look it up on Google" is a poor argument"
I agree.
"redlining is denying a loan based on membership in a group rather than on individual merit"
I think you need to look at the original term - redlining. They took a map and drew a red line around certain neighborhoods or areas and refused to do business there. Sort of like a pizza place that won't deliver to everyone in town, but only to certain neighborhoods. The residents of a redlined neighborhood make up the group - all of the residents, black, white, whatever - if you live there they won't do business with you. Unless GE is refusing to loan money to some gun businesses in a town and not others, I don't see that redlining applies.
While I agree that in the original meaning the group was defined by geographic location, in the broader sense the injustice was caused by denying credit to a group instead of individual merit. So if you don't want call it "redlining" because the discrimination isn't geographic I'm open to suggestions as to what this new breed of discrimination should be called.
It's still wrong by any other name.