I don’t see this as an American thing. It’s an extension of the current Product Management trend to give software quirky and friendly personality.
You can see the trend in more than LLM output. It’s in their desktop app that has “Good Morning” and other prominent greetings. Claude Code has quirky status output like “Bamboozling” and “Noodling”.
It’s a theme throughout their product design choices. I’ve worked with enough trend-following product managers to recognize this trend toward infusing express personality into software to recognize it.
For what it’s worth, the Americans I know don’t find it as cute or lovable as intended. It feels fake and like an attempt to play at emotions.