I think I've finally settled in my mind why Wilbur saying "I never cared about L'manberg" doesn't ring true.
It's not that I don't believe him, because, with that line as context, looking back, it's very believable; it makes sense that he was interested in it as a way to "stick it to the man" during the rebellion, It frames his desire to call an election as a certain dissatisfaction and insecurity with his own power, and It puts his blowing it up into a new light.
Wilbur also loved L'manberg.
He loved it. He wrote to Phil with designs for the flag. He wrote an anthem. He risked his life and fought a war.
"L'manberg, my unfinished symphony--" is not the anguished declaration of a man who does not care.
And the disconnect that both the audience and Tommy are having with these statements, is in the fact that Wilbur isn't lying.
But he is omitting something crucial; Why.
And the answer is, ironically, people.
Wilbur didn't care about the nation he was creating, it could've been anything, anywhere - but he cared about the fact that he was creating it with Tommy.
He cared about the fact that Tubbo jumped at the opportunity to help them and supplied the materials for the first incarnation of their walls.
He cared about the fact that Eret spent hours refining and building the walls out taller and more beautiful.
He cared about the fact that Fundy was born within those walls.
The walls didn't matter. It wouldn't matter if someone built them back up overnight, and restored L'manberg to it's former glory and served it on a silver platter to Wilbur.
So, so similar to Ranboo, but also fundamentally different, is how much Wilbur believes in people, and how he sees them as inextricable from sides - he knows how powerful the allure of a cause to believe in can be, and he's been on both sides of the dangerous fallout when people stop believing.
A side is, ultimately, a way to find your people. If you're on the same side, those are your people. The L'manbergians may have been brought together by a man who didn't care about the land, but they didn't join for the land. They built the land. They joined for Wilbur, because they wanted to be on his side, and he was on theirs, and the form that took was a nation.
And likewise, the thing that destroyed Wilbur wasn't the loss of L'manberg - it wasn't losing the elections that got him in the end, it was his people; abandoned, betrayed, forgotten.
L'manberg is his unfinished symphony not because the walls fell, but because Fundy tore them down; not because Schlatt was on the podium, but because Tubbo was killed there; not because Tommy didn't want to follow him anymore, but because Tommy didn't believe in him anymore; because Eret (wilbur) pressed the button.
L'manberg started as a drug van that got busted by men who were stronger than they were.
L'manberg started as an uphill battle against men who set their forests on fire after they declared they used words and not weapons.
L'manberg was a way to stick it to the man.
(The man had more of a problem with Tommy than he ever did Wilbur.)
Wilbur never cared about L'manberg.