It's not powered by AI though. It's just got a bunch of teasers and upselling ads for AI cloud services. Doesn't really have much to do with the OS.
The same with office, there was no point in renaming it to Copilot especially because the standard license doesn't even come with the Copilot features in office.
Personally I don't care what they name their services because I've already determined I want nothing more to do with them.