I once thought (incorrectly) that .ws domains were going to be the new hot thing since I failed to appreciate how other TLDs would allow emojis and thus, make none of them actually worth anything.
To answer your question: Yes. I thought ruby handled it automatically, but it turns out that, no, you need to actually do fiddly stuff with some of the emojis like this one:
https://emojipedia.org/man-raising-hand-light-skin-tone/
In general though, emojis are more complicated than people give them credit for. There was one domain I had that you could only type on Android and not iOS! The exact encoding for one of the emoji slightly differed. I can't remember all the details, but emoji is annoying and best to be avoided if you can.