There are many types of channels on Twitch with all sorts of different people and communities. Some of them are toxic, yes, but in my experience of being on Twitch for two years, most communities are filled with amazing people and I have met a lot of real life friends through using Twitch.
Anyways... Twitch does have "$msgtags" that do contain the user's display name ($msgtags(display-name).key). However, with the script in question, you are "shouting out" users that may have not typed anything in chat, therefor you wouldn't be able to check the $msgtags for the display name. Because of this, a simple call to the Twitch API is sufficient and also doubles as a way to verify that the user is valid (in case a moderator types the name wrong by accident).
