'I converted to a republic and then did a bunch of other stuff and then ended my game through an illegal capital move'
It wasn't illegal, it's a valid capital move. I didn't cheat or exploit.
The game ending message was: "You have converted to a Republic, and therefore cannot play",
not "You have moved inland, and therefore cannot play". So if you want to complain about my semantics, why not aim your complaints at the people who wrote the game-ending message?
Also for your benefit, the definition of therefore:
Adverb - for that reason; consequently.