which isn't going to do a lick of good for the island
And what makes you say that two realms, one with a city and one with three cities, is worse than a behemoth with 4 cities?
They simply don't have enough as they took quite the loss being defeated by Luria earlier this year.
A bit of a conclusion jump? The players didn't leave from being defeated by Luria. They left because they refused to do anything afterward and bored themselves to death with inaction. You can't keep expecting the game to entertain you, you have to act yourself. There were opportunities for them to do something, but they intentionally limited what they would consider doing.