This is some business writing that keeps things simple and I love it.
To be an airline is to be in an almost uniquely terrible market position. For starters, there are only two makers of aeroplanes (Airbus and Boeing). For reasons of training and staff efficiency, you have to commit to one or the other, which gives the aeroplane makers very strong pricing power.
And buyers of airline tickets are incredibly fickle and have no loyalty. They will switch from one "carrier" to another over even small differences in price. Annoyingly, there are loads of other airlines and they're all running the same routes as you!
Worse yet, starting a new airline is surprisingly easy. Aircraft hold their value so banks will happily lend against them. There are loads of staff available that new entrants can hire. So randos will continually enter your market, often selling tickets below cost for quite a while before they go bust. And to top it off, there are plenty of substitutes for air travel - from government-subsidised high speed trains to Zoom calls.
Airlines that get more efficient, work harder or come up with innovations aren't going to be able to "capture" the value of what they've done. If you make more than the bare minimum to survive Airbus will notice that you're being undercharged and you'll find that the next renewal on your service contract eats up the difference.
Being the Coca-Cola company is pretty great though.
Coke is just water, colourant, flavouring, caffeine and sweetener. Those are all widely available and really cheap. And as I said, you don't even have to combine them yourselves - bottling companies will do that for you for almost nothing.
Handily, consumers are really picky about what goes in their mouth. The unofficial motto of your main competitor is "Is Pepsi ok?". This is despite the fact that they are identical in both taste and colour. And a significant minority of people actually say no!
And it isn't easy for new competitors to enter the market. They can't call their new drink "coke" due to trademarks. They have to call it something else. And consumers will generally refuse it because drinking an alternative is considered some kind of weird statement.