Does it matter whether something is new or not? The fact is there are services such as AWS lambda that people are using and talking about, so we need terminology for that.
Take NoSQL which was hyped as something new 5 or 6 years back. Because of that everyone under a certain age decided that they had to use it.
The older more cynical of us realized that this was how people has been writing software before SQL came along, and realized we were throwing out a whole host of features and benefits because this was the "new" way of doing things.
Then call it function hosting or business-logic hosting. "Serverless" means "there is no server" which is demonstrably false. Or should I assume that words don't mean things?