You’re in a self-contained, pressurized environment. What IF there is a freak spark? couldn’t that lead to a major problem? Even though whatever is in the polish is of small quantity, wouldn’t the pressurized cabin magnify things? I’m not equating it with what happened aboar Apollo 1 but couldn’t a smaller scale Apollo 1 type event be possible under those conditions?
Airliners are not full of 100% oxygen. A spark is not going to explode nail polish in a airline cabin. Come on, has our bubblewrap society forgotten that 30 years ago people smoked on airplanes, hence the ash trays you still see in older airliners. The lady is rude and inconsiderate but the only danger is that someone will smack her upside the head and tell to have some manners.
I wouldn’t know enough to comment on the possible fire hazard, but I’ve experienced the pleasure of being in the same plane with someone doing her nails... kinda like that guy rudeboy posted...