Yes, it is ignorance. What you described in your first couple of sentences is ignorance. It isn't a four letter word or a judgement on character, it's just something that's good to be rid of. Maybe some commenters have friends with CP who are ignorant of what the word gimp can mean because it isn't used that way where they live. That's fine for them but their ignorance (again, no aspersions!) doesn't change a thing. Also, I'm not casting aspersions on the developers at UC. I dont know why they picked that name and its not germane to what I'm saying.
On a lighter note, I'm touring the US right now and yesterday passed a beer store that advertised that they'd fill your growler. So yeah, language can be funny. It's good to be aware of how it can be funny and who your audience is.