I’d say хз (the last one) is still used very commonly, but the rest are a bit outdated and I barely see them anymore.
Another thing I thought was outdated but some of my friends use is shortening common words. “I like” would be “мне нравится” and some people save themselves a second and write it like “мне нрав”.
And another thing I just thought of is “etc” equivalent in Russian, “и т.д.”, this one is used officially in documents etc, it’s a shortening of “и так далее”, literally “and so on”. And some people simplify it further by writing “итд” without spaces and dots.
And also, isn’t Copilot in other MS products besides Windows as well? Even if not now, it could be in the future. This naming would make it limiting to expand.