The highly educated and elites tend to act as you say, yet note every time the Euro-Union puts up a vote the Danes, Irish etc vote NO. The Sollies would have to treat Earth as Nazi occupied Ukraine to blow it big time. (which indeed is not impossible).
I put the 'Impify' in quotation marks for a reason. I'm not suggesting that Terra, in 1110, had come to identify with the Imperium. But, except for the lunatic fringe that all societies suffer from, they had reached an accomodation with it. Left to itself, it would undoubtedly have continued to think in term of us and the Imperium (Though there's no reason to believe that, absent Solomani Party goons and Solomani Cause education, they'd identify with the Solomani cause either). But they weren't left to themselves. Think about it for a moment. How would the British feel if they were invaded by the EEC, became sufficiently reconciled to them that the occupation was lifted and the occupation troops went home, then 'liberated' by America
and kept occupied by the Americans? Do you really think that the relative benevolence of the occupation troops would matter? The Germans treated Denmark with kid gloves during the first half of WWII, and opposition still kept growing steadily.
EDIT: Even better analogy: How would the Scots react to being liberated from England by the French (The Auld Alliance, you know)? The Scottish Nationalists might be happy at first, but what about the general public? And how long would the Nationalists stay happy if the French stayed on and began teaching them to be proper Catholics? (I know the last part is a bit of a stretch, but fanatically held ideology is not that different from religion).
Common people told their kids Vilani are sub-human and they are a master race, they tell their kids so on and so forth. So the commoners fed on home stories of Wolfe, Alien envy, Terran Supremacy and 1st Interstellar Wars will easily assimilate while the elites who see the Imperium as stable and less jack-booted will flee or get sent to the 'camps.'
Danes no longer hate the Swedes for stealing Scania from us, despite whatever atrocities they committed. AFAIK the Scanians themselves no longer hate the Swedes and don't consider themselves to be Danes any longer (except for a small "lunatic" fringe (I put that in quotes because I think even the fringe is being tongue in cheek)). A hundred years of abuse may keep hatred alive easily, but a hundred years of decent treatment is a long time. Who on Terra would care about the Invasion? We Danes don't even care about the reaming the Germans gave us back in 1864 any more (not much, anyway

).
Hate is learned at home! 100 years is not enough there are still a few alive who remember the Rim War.
A hundred years can be enough. A generation can be enough. And, as I keep pointing out, the Imperium wouldn't have lifted the occupation if it hadn't been enough. Where's your evidence that the general population of Terra taught their children to hate the Imperium? A small fringe of Solomani fanatics, sure, but not the general population.
Hans