I'm a little confused by all this talk of "othering" people. Ethnic backgrounds differ. Countries with similar ethnic backgrounds differ, even if not identifiably (as in people from two countries might look similar, but their countries are very different from each other culturally). Why is noticing that someone is different immediately make you a racist asshole? Isn't the whole beauty of human existence the fact that we're all so different, but have so many threads linking us at the same time? Why is pretending that everyone is exactly the same helpful?
Because:
1) it's up to the person who differs to celebrate their differences. I'm out as sort-of-kind-of-bisexual, but I know plenty of bi people who don't want to discuss such matters with just about anyone. I am comfortable with my nationality, and I've joked about it, and I've had American friends make "polack" jokes in my presence. But if someone commented on my nationality, even in neutral or positive terms, unduly? I'd be probably a little miffed.
2) When people bring up differences, it's often to harm someone.
3) Even when they don't want to harm someone, they have privilege (often to troubling extents) and that often shows. In other words, when a person belonging to the dominant/majority group addresses that fact, it's often at the very least awkward and uncomfortable, because they don't know what they're talking about. And, notably, they often treat their perspective as the default or valid or important one, even unconsciously.
4) When a white person brings up race, or a straight person brings up homosexuality, they do it on their own terms. They engage with something they do not otherwise HAVE to engage with. A POC or a lesbian or an immigrant doesn't get to pick and choose when and how they engage with their minority status. That's why they should be the ones to do the framing and take the initiative.
And yes, I'm aware of the staggering irony of writing 4) as a white, mostly straight, mostly cis dude. Since I've about run out of the little I know about othering and discrimination, because I've only experienced it in extremely minor ways...
...I think I'll let peple who, unlike me, know what the f'k they're talking about take it from here.