Man has to stand for 7 hour flight due to fatty next to him.

[Low C Sharp]

I had also thought it was kind of an unspoken understanding that nobody actually use the armrest, but rather keep your elbow in your own lap.

Hm, I choose window seats, and I never begrudge the armrest to the person in the middle. IMHO, the shared armrests ought to belong to the middle seater -- though this doesn't work on widebody planes with a row of 5 in the middle.

I'm interested by the article, though I question the author's request that airlines need to make accommodations "without surcharging the people who require slightly more space than others." If you need more baggage space, they surcharge you for it. That's true even if you are carrying the extra bag for an important reason that outside your control -- even if it contains your samples for a sales trip or mementos your dying mother requested at her bedside. More space and weight, more money. Why shouldn't we all be able to pay for more seat space, regardless of whether we are big or small? There are lots of short people who are happy to pay more for the extra legroom United offers on Economy Plus. (As far as I know, that's the only major domestic carrier that has this option.) How can the author know that a given smaller person is necessarily less comfortable in a small seat than a given big person? Some small people have claustrophobia, back pain, etc. that might make their flight far more miserable in a tiny seat than it would be for a big person without those problems.

Also, it's not about the amount space the airline has arbitrarily decided we "deserve" -- it's about the amount of space that they offered for sale and that we agreed to purchase. If you want more than what is on offer, pay more. No other consumer product is discounted on the basis of need.* I just don't agree that any customer has the right to fly at the very cheap prices we've gotten used to in the 2000s. 30 years ago, we transacted plenty of business and people got to their mother's deathbeds just fine even though flights were far more expensive. In real dollars, two seats on Southwest today is cheaper than one seat on TWA in 1980. We all got by.

*If you live in a snowy rural area and you need 4WD on your truck, the dealer doesn't give you that upgrade for free because you need it, while it would just be a luxury for city dwellers. Sometimes our needs just cost more, and we can't expect merchants to eat that extra cost for us.