You're citing a reddit thread for a legal principle. No.

> Unless the derivative work falls under fair use, the rights-holders can use it however they want.

Unless the derivative work falls under fair use, the rights-holders can stop you.

Let's make the case as clearly as possible. Microsoft incorporates some clip art into Windows without a license. Does the artist of the clip art now have a right to start selling copies of Microsoft Windows to everyone? Of course not.

As completely bonkers as it sounds, you are probably in the wrong here.

So, just for background: you're basically right to sense that the fundamental thing in copyright law is the right to impose lawsuits to stop infringement. (We could add to this "or to collect damages", is the only major missing part.)

Restating the person you're replying to (in this vocabulary), you responded to "you can't stop the rights-holders" with "the rights-holders can stop you." This appears to be a total non-sequitur; I guess the most charitable interpretation is, "They cannot use your work however they want; they can merely stop you from using your work in ways that they don't want." The first half of that is wrong even though you only stated the second half of that (which on its own would not be particularly objectionable). Some peeking at the paragraph afterwards seems to confirm that this is what you meant; again that paragraph is OK by itself without context but is being used to support a wrong point in-context.

So here's why that paragraph is factually correct but doesn't make the point that you want: the US copyright law treats every derivative copyright work as made up of hypothetically-clearly-defined "parts" which each have one or more copyright interests in them. The judge in the case would probably not say that the "part" which contains your clip art is the whole of the Windows operating system; and Microsoft would retain its copyright interests in the rest of Windows while losing it in the "part" which was your clip art. This matters because it means that there is only one copyright interest on that part (yours) rather than two (yours and Microsoft's). So if Microsoft added a monocle and top hat to your cartoon-face-shaped-like-a-bean, you could in fact probably use their version without fear of a lawsuit (though again, some judge might say that, say, the top hat is sufficiently differentiable from the beanface that it is a "different part" of the derivative work).

What? No, that wouldn't make Windows a derivative work. We're talking about derivative works here. The 'reddit thread' I linked to isn't important; the point was that someone made artwork based on a TV show, and had that artwork turned into a Tshirt that is now selling at Hot Topic by the creators of that TV show, without having any choice in the matter. In other words, they have no claim to their artwork because it is a derivative work.