This is becoming so common that I am starting to wonder if it's intentional, to erode and dilute the actual meaning of "open source."

There have been a spate of startup products that advertise themselves as "open source" to capitalize on the marketing/SEO advantages of doing so. And when called out on this in comments or whatever, the founder eventually presents some kind of argument along the lines of, "well if anyone can read the code then it is open!" or even the old "language can evolve" canard that people trot out when they want the meaning of a commonly-understood word or phrase inverted to fit their specific business or political agenda.

People "conflate" the two because that's the logical implication of the phrase when one does not have the historical context of living through and being aware of the early days of the open source movement. Words do have meaning. You're just adding additional meaning to them that is not commonly understood.

Attach the same adjective to "park" or "road," and you'll understand my frustration with people claiming dominion over the word, "open." You don't have an obligation to cut the grass or fill a pot hole.

If you want people to understand what you mean, use more specific language like, "copy-left." That was a fabrication of the open source movement and doesn't clash with commonly understood language. If they don't already understand the jargon, at least it will be obvious, and they can seek out the definition.

No, I don't care what some open source foundation defines it as. I don't recognize their authority to extend the definition of the word, "open."

> use more specific language like, "copy-left."

But copyleft already means something different from open source. It's more like what people unfamiliar with open source software think that open source software is.

Exactly. AT&T Unix was the quintessential example of source-available software. Companies and institutions could get licenses for the Unix source code, but they weren’t allowed to redistribute it, and it certainly wasn’t free. If I recall correctly, while it was originally only $99 for academic institutions, the price went up by orders of magnitude after the breakup of AT&T (before the breakup it was prohibited from monetizing Unix due to an agreement made with the US government when AT&T was involved in an anti-trust case).

We wouldn’t have our modern BSDs if it weren’t for people being frustrated with source-available Unix. BSD initially started out as essentially a collection of additions to AT&T Unix. Eventually after the divestiture of AT&T and the resulting dramatic price hikes for Unix source licenses, the Berkeley developers embarked on a campaign to replace AT&T source code to develop a fully open source Unix. They beat GNU to the punch (see GNU Hurd), only to be stymied by lawsuits from AT&T.

Your analogy actually shows why “open” is appropriate in this context. It’s true, you don’t have to cut the grass or fill a pothole in an open park or an open road. Similarly, you don’t have to fix any bugs in an open source software either. But if you do, you cannot stop others from using the fix. In your analogy, if you do fix a pothole, you cannot prevent other road users from using the patched portion of the road.