While it's going to apply to some specific communities:
> When you migrate to a new country you just naturally get into a bubble of your nationals.
Just keep in mind that's a really bad generalisation. There's different groups migrating for different reasons with/without a family. You don't "naturally" get into any bubble unless you seek one, or have an existing connection to.
When I say "naturally" I imagine the situation, when you stand in a "social desert" and there are two people in front of you. They are the same age, the same profession etc. But the first one is from your native country and the second one is local. In order to communicate with the second person you need to use language you are not native in. There is also some cultural/mentality difference, naively you are not sure which topics you should avoid in discussions. Obviously you will feel a lot of pressure, at least in the beginning, speaking with the second person. When there are no such hurdles between you and your person. You can use your language, you know where the social borders are etc.
In order to make a connection and support it with the second person you need to overcome those hurdles. They may be not big for you. But my point is that they are there. And if human has a choice they naturally chose the easy past.
My point is that if you migrate you rather need to seek (work on) making friends with locals.
When, surrounding yourself with people from your country will happen by itself.
Of course I do not know what is the situation for everybody.
But this is what I see around me.
It sure happens, especially for the secondary people (family migrated because one person got a job). But I disagree with this as a generalisation. There's people who move explicitly to get to the new culture, those not connected to their home country, those just curious for something new, etc. I migrated multiple times now and I've seen lots of variety. You'll run into people from X who move specifically to the Xs neighbourhood, and people who resent X-specific meetings. It's really preferences and situations and many are shared/common but not something "natural".
Keep in mind that it's easier to see the number is Xs hanging out together in an Xs neighbourhood than how many random Xs are there individually in the city. (That you may not even realise where they come from)
> When you migrate to a new country you just naturally get into a bubble of your nationals.
Just keep in mind that's a really bad generalisation. There's different groups migrating for different reasons with/without a family. You don't "naturally" get into any bubble unless you seek one, or have an existing connection to.