Yeah, and all but one of those claims is incorrect.

"Open source" is not just a turn of phrase which became common over time. The phrase was coined by the founders of the Open Source Initiative, and it has always had a very specific meaning: https://en.m.wikipedia.org/wiki/Open_Source_Initiative

People who seem to think that "open source" has a variety of meanings, are probably confusing it for "free software" which does indeed have a variety of meanings (which was the whole reason the phrase "open source" was created - because "free software" was too vague, and they wanted to create a term with a single, specific definition!)