This is not how airlines are operated. In many other countries you get one or two checked bags included in the ticket.
A strange thing occurs as a consequence: you just board the plane, and then the plane goes.
Do you do the weird not-a-queue-but-queueish-blob-of-people thing? No, because there is not a zero-sum game for overhead space.
Do you do the pay-extra-to-spend-longer-in-the-hell-tube thing? No, because there is not a zero-sum game for overhead space.
Do you spend 45 minutes to an hour fucking around with idiots who are trying to spit in the face of both geometry and physics and falling arse-first onto the nose of good manners? Not at all, flights are typically on the runway 15-20 minutes after the first boarding call. There is not a zero-sum game for overhead space.
When I first flew in the USA I thought "something is wrong with my flight". It took me several flights to realise: this is normal here. And it's maddening.
In every flight I find plenty of people (myself included) that don't want to check in baggage, due to mishandling, possibility of loss, delays at the destination, and/or problems with connections. So even in airlines where you get a checked bag with the ticket, I regularly see all those things you say don't happen. Maybe it depends on which part of the rest of the world. I'm from Spain, for the record. At the Madrid airport you will see plenty of people queuing at boarding gates half an hour before they open. Most Spanish airlines even have a paid "priority boarding" option to board first, so people very much want to get into the hell tube sooner...
It's true that all of this is amplified for airlines that charge for checked luggage, though, so I'd rather they don't charge even if I don't want to check in myself. Competition for overhead space gets absolutely crazy when they don't charge.
My point about carry-on is that in other countries, you are strictly limited in what you can carry-on, and thus you either have to take less stuff or get checked luggage (free or otherwise). And guess what? Everything fits and people can just walk to their seat and sit down, as you described
I fail to see why the US has a system where everyone is allowed to take two giant items, and then without fail half the plane has to gate-check and it causes significant slowdowns and frustration. It’s like smacking your head into a wall repeatedly, wondering why your head hurts, and continuing.
I can see why people don’t want to check; short flights for business as so much faster when you don’t have to wait for the baggage carrousel or lost luggage. But when you’ve got a 50% chance of being checked anyway, everything breaks down.
In other countries, the carry-on limit is strictly enforced. They have metal frames to test the size of your luggage, and if it doesn’t slip in, you ain’t taking it on the plane. And a “personal item” isn’t allowed to be a second bag the size of a carry-on suitcase.
If you have too much stuff, tough. Either take less crap or get checked luggage.