It's been a few years since I watched Airplane, and while I absolutely love it, I recall it being rather tame even by modern standards. I can think of a few gags that might not land as well today, but I don't think it was mean-spirited.
When I watched it recently the joke that kinda flops is the heavily stereotyped gay man. Whether it is offensive I have no idea. Its not flattering.
Sure, the old white woman using heavy black slang is where the joke comes in.
I don't get it does that make her a racist or something? She tries to help.
The joke is: their slang is so heavy its another language.
Personally make fun of zoomers all the time for this.