No, it would be open source. There's the source code. It's open; anyone can go look at it. Whether or not you can modify it without violating a license has nothing to do with whether or not you can read it.
That article describes this as a misunderstanding:
> The official definition of “open source software” (which is published by the Open Source Initiative and is too long to include here) was derived indirectly from our criteria for free software. [...]
> However, the obvious meaning for the expression “open source software”—and the one most people seem to think it means—is “You can look at the source code.” That criterion is much weaker than the free software definition, much weaker also than the official definition of open source. It includes many programs that are neither free nor open source.
> Since the obvious meaning for “open source” is not the meaning that its advocates intend, the result is that most people misunderstand the term.
That is, Stallman is criticizing "open source" for being, among other things, easy to misunderstand as not requiring free software licensing — even though it does, in fact, require free software licensing.
That's not the OSI definition, and your Richard Stallman quote isn't saying what you think it's saying.
It's saying that one of the problems with "open source" is that you can make the same mistake you just made (thinking that being able to see the source code makes it "open source").
Richard Stallman's primary issue with "open source" is that they intentionally avoid talking about issues of software freedom, and have consistently muddied the waters by co-opting free software as "open source".
And this is exactly why Richard Stallman doesn't like the term. https://www.gnu.org/philosophy/open-source-misses-the-point....