There's a say whether a community wants to accept or not the migrants though. If we step away from nation states and imagine a tightly-knit communities based society, one wouldn't be able to settle in the community of higher abundance and security without being accepted by the community members.

The ""communities""" you talk about are an old fashioned concept that don't really exist anymore. For context, in most big cities, a "community" would consist of 60-80% immigrants, expatriates, seasonal workers and more types, with the minority being the ""locals"". So this is a non starter anyway. Remember that in smaller communities, newer folks would not want to fit in anyway. They would prefer to form their own tribe. Nation States as we know it are dying a slow, but sure death. It's only a matter of time as they decay and rot...

I wouldn't agree to the claim that geo-based communities won't exist. It's the only thing that captures the peculiar, shared exposure that the inhabitants face as steakholders. This shared exposure unites them and incentivises cooperation in decision making and policy.

National state borders are the natural state. People build their community and share common values and abilities. Different communities have the right to protect their people and the value they created with their effort and diligence. We have the right to stay with our own people without being invaded. We will fight to death for that right. Fuck communism and internationalization