When I was a kid in Australia decades ago we'd never heard of peanut allergies and swapping peanut butter sandwiches at school was the norm. No doubt there were allergies back then but what on earth has made them so much more common these days? Same with asthma. Something has gone terribly wrong.
I saw a show several years ago that said Australia (I think specifically Melbourne?) and a city in Finland are the epicentre of research for food allergies, because of how prevalent they are. The Finnish two was basically split in two decades ago so that half of it is in Russia and half in Finland. The Finnish side has made significantly better economic progress since then, but also has a much higher rate of allergies. In Australia it seemed to affect first generation descendants of immigrants (I vaguely recall SE Asia and South America being over represented in those impacted?). They had a doctor from Malaysia on the show that had 7 kids, the latter 2 both born in Australia and both had peanut allergies. I remember him saying how hard it is to travel home with them “you tell someone in Malaysia your kids are allergic to satay and they just don’t understand”.
I’m like you re lunches as a kid. I never liked peanut butter as a kid, but it was a staple option among kids alongside Nutella and Vegemite. Now peanut butter and Nutella is banned in a lot of classrooms.