given those "facts" you posted, how come people have had severe reactions on planes and other closely confined spaces?
I have looked around Dr Google and cant find any studies that confirm airborne nut dust can cause allergic reactions. However I can find many that show it can't. Nut allergies do exist and those having severe reactions (on aeroplanes) must have come into direct contact/eaten them.
Given around 1% of people have nut allergies (not all severe). Then given how many people fly every day and 'open' a packet of nuts on an aeroplane, we would surly be hearing of people reacting/dying of nut allergies every day. We don't.
Will banning nuts help this? Well without any evidence to show it will, how do we know it wont make the problem worse? Could it lead to less people eating nuts and more people becoming allergic to them. Could bans means less money is spent researching a 'cure' to the problem. Could bans mean any food made in factories that also make nuts also be banned? Could bans mean more nuts are eaten/disposed of in the airport and the risk of direct contact with nuts be increased?
And what about food that people bring on board that 'might' contain nuts. What about fish allergies, which are four times more common and can also cause anaphylaxis, will we ban that as well? Will all food be banned?