The problem starts if it is that small bite of a donut or nothing.

Or in IRL terms

"We hate our elites, but they are ours and ours to hate. We won't replace them with RuSSian elite at any cost. They are badtards but they are our bastards."

So I would put more money on demands for UK to pay restitution for Jalta (and France geting one for Trafalgar for humor) than on any, even smallest concessions.

As to UK...there will be no appetite for special treatment from EU.

They should expect at best special humiliation as the rest of EU will look at them as unreliable country. Plus all of CEE countries may be very very vindictive after those Brexit headlines about us eating swans and what not.

I would argue we have more than enough research to prove cooperation is rational, economical and highly effective.

First bigly example: Nazis

So individualistic might makes right that do to infighting they lost economically even to Stalin USSR...

Not to mention it lost them the war much faster.

Oh boy.

1920s Germany make USA of today look calm, collected and safe...

There were so so many reasons for zeNazis and at the same time so many other possible bad outcomes...

Problem starts if it is both.

And many times it is partially common good and partially keeping elite in position...

And then it can be a choice of do you want to do a MAGA/Brexit to screw the elites/others over and ignore it can be much worse for you while only a tad inconvenient for 1% at the top

But people can be willing to a accept losses in living conditions in times of war or when national/imperial pride is on the line.

See "We want eight and we won't wait!" and other famous arms races of that type.

Hmmm an extreme example of getting your neighbours pissed at your Make Germany greater again project...

Both a return to an old "Empire of greatness" that ends like most such endeavours in getting your neighbours pissed at you, your economy shoot by yourself in foot or two...

Plus being shown as an example what not to do with a practical lesson of consequences...

Yes, but even Hungary is ready to kick RuSSia spy balloon out when they became poorer than Bulgaria and Romania.

It is not only economy or voters personal situation.

Sometimes it is national pride and a yardstick for "how good/bad is our countries power" with a bit of old historic rivalries.

But then we would need to

1. Program them not to eat deserters, defectors, spies, Ukrainians, refugees etc.

2. We wouldn't get a daily quota like Ukraine.

3. Viewing platforms would be much less safe. Works still have huge piles of ww2 artillery