Honestly, I've flown a lot (to 100+ countries, I'm sure). You can take food on planes. It's a thing. No, you can't take:
(a) sandwiches made out of endangered species, or really any form of barbecued animal covered by CITES.
(b) don't attempt to get around this by keeping the live version of the animal in your hand baggage for inflight slaughter and preparation. (Exempted in some former Soviet republics.)
(c) food made primarily out of liquid or food that's been around so long that it has turned to liquid and made some progress towards sentience.
(d) peanuts, obviously, as even undetectable levels can be fatal to people who aren't even on the same plane.
OK, they might frown if you turned up a doner kebab as they smell like someone has heated up a month-old dead badger unless it's dark.
I've done a deep analysis of the available stats – no one has died of starvation on a plane. Airline food is far more likely to kill than it's absence.
Airlines are pretty willing to bend to get you your halal, kosher, gluten-free, dandelion-free meal, and the QC of their supplier will always ensure it tastes like chewed cardboard and despair regardless.
Travelling by air is a festival of bad food, tbh, from the endless airport concessions (businesses you are often sure went bust in the outside world) to the lukewarm inflight 'pasta or chicken' (what actually is it? I think it's brown, sir).
I think, tbh, it's a bit of privilege of modern life in a first world country to be able to eat what we want when we want.