Comment by IggleSniggle

Correct. So, you can emphasize your new identity as an "emigrant from A" or as an "immigrant to B." "Expat" goes one step further by not only emphasizing that you are an emigrant from A, but also that you are no longer a political participant or under the authority of A. It is not semantically incorrect to call yourself an "expat" if you are an expat, nor would it be semantically incorrect to call yourself an emigrant from A or an immigrant to B.

I'm attempting to pin down why some people might feel that someone calling themselves an "expat" has some negative connotations for the expat. It doesn't have anything to do with the correctness of any of the terms involved.

To say it a different way, I think people find it distasteful because it focuses on the political shapes you no longer are bound to, rather than who you are "now." It's normal to celebrate your cultural heritage, but it's kind of odd to focus on your status as a non-member of your former state.