Is expat a dirty word?

I was scrolling Instagram the other day (as you do), and I came across a video that was about an element of expat life. The video itself was benign, but the comments were anything but.

Yikes...

It got me thinking–is expat a bad word? I typically refer to myself as an expat because I know that I'm not here permanently, and I'm only able to live in Japan as long as job opportunities present themselves. I always thought of immigrants or migrants to refer to people who were planning to set up life permanently in a new country, but maybe that's not the case?

Alas, I was wondering about the opinions of others here, since this is a site geared towards expats! Do you refer to yourself as an expat, or a migrant or immigrant? If so, are there reasons why you use one term over the other? Let me know in the comments!