[kosciusko51]

I understand the economics of the situation of smaller seats, but it is contrary to increasing size of passengers. Thirty years ago, I was one of larger passengers on a plane. Now, there are a lot more passengers bigger than me. And yet, the seats get smaller...

[circlecity]

"I understand the economics of the situation of smaller seats, but it is contrary to increasing size of passengers."

The airlines won't care about passenger comfort until it starts costing them money.

[Blue Jays]

The only "arrow in the quiver" is for travelers to halt using airlines that they find uncomfortable.
Perhaps use trains, rental cars, private jets, videoconferencing, or other means to meet with other people.
If jetliners become empty due to comfort issues, they will begin to change to lure people back into the seats.

[TexasGunLover]

but it is contrary to increasing size of passengers

Irrelevant factor. Revenue is the primary factor. (I've been in the airline business for 20 years).