There is a lot of truth to this.
Having said this it helps you in terms of personal growth to immerse in another country, culture and language as much as you can. (If you view it as a challenge that you enjoy taking on, and you enjoy the target culture.)
One observation is that cultural distance is not always proportional to geographic distance: for instance, there are things that German and Japanese culture treat identically that British culture treats very differently.
Being an expat may be hard, but being an ex-expat is easily as hard or harder: returning after extended absence, and expecting things to be the same, you will find out that people have moved on, and that the good things that you were missing (perhaps over-idealized) may no longer be good, or may never have been so great in the first place.
"You can never come home again."
-- Bill BrysonKudos for OP for writing this, definitely a view point which is under represented. To be the 'perpetual other' is a strange experience, not always unpleasant, but always somewhat insecure.
Similar sentiment shared in this week's NY Times: https://archive.md/WwK1J
my .02, I had a great 3 year expat experience. I think the difference was I was young and in a large city. While I certainly connected with many locals, other expats from many different countries formed my core friend group and I was often inviting local colleagues out with us.
I've seen this said before, especially of the Dutch. A high tolerance for Anglo migration but also a very intense sense of "dutchness" which is very hard to acquire as an adult and as the article notes you lack the familial and school links which bind people.
A guide book I read before a six month residency there said sometimes locals need to be themselves and not deal with you as an incomer.
I know this experience is not universal, but I do think it is underrepresented.
> Perhaps your life failed to launch, and moving to a new country could genuinely help you restart from a difficult situation.
I caution against changing countries to fix your unhappiness with life in general (unless you really are from a disaster area). If your general approach to life leads to grief, you will just be taking it with you to a new location. I've seen it often enough.
Some of the angriest expats I knew in Japan were Japanese Americans. They had felt rejected by American society, so went to the "old country" in search of belonging. The native Japanese just regarded them as Americans, so they ended up feeling doubly rejected.