This is not a serious argument. Lots of people don't have the means to simply up and leave. There is also value to continuing to fight from inside the belly of the beast. If nothing else, those on the inside can do far more damage to the machinery of empire through sabotage and direct action than those from outside can do.
This does however take the willingness to take great risks and put your life and what little is left of your freedom on the line. It takes a recognition that a) change through reform is fundamentally impossible in the core and social democratic concessions serve the purpose of pacifying and bribing the population with the spoils of imperial violence, and b) that a revolution in the core will not be possible until conditions get much, much worse, and until then you are simply a "man on the inside" for the revolutionary forces in the global south whose duty it is to agitate the imperial core population against their own government, to sabotage as much as possible the machinery of empire and chip away at its power to suppress revolutionary and anti-colonial movements in those places where most of the revolutionary potential exists right now.