It's simpler than that. A house has to be to code for the year it was built, end of story. If the panel was directly above the kitchen sink and code was ok with it then, it's good until the end of time. It may be suggested a correction be made but they can't require every house out there be rebuilt every time code changes. Afci didnt make nec until 98 to begin in 02 if memory serves. I deal with 'code' roughly every day, it's not hard to figure out.
I'm the only gay eskimo.