"SQLite is serverless" is by no means a meaningless buzzword. The term had a clear meaning before it was coopted by the current web dev fad. SQLite does not operate on a client-server architecture the way e.g. MySQL or PostgreSQL do.
A quick search of usenet shows "serverless" being used in 1994. It wasn't a term or a buzzword, it wasn't common, it was just English: https://groups.google.com/d/msg/comp.os.linux.misc/r76oNl98C...
That was never a common usage of the term serverless.
Software development didn't begin or end with web dev and the cloud.