Yup - and that’s the point of the comparison. They share a lot of important code (mostly in the userland IIRC), and yet people don’t consider MacOS a BSD, since both drifted away so much that lumping them together is simply not useful. And yet it’s what the author is doing with ChromeOS and Linux, that are in the exact same situation. (Another way to say this is how you did it - they don’t work the same and you can’t use one to do the things that makes the other worth using.)
I thought the author’s point was pretty well-made.
The author’s point boils down to “actually you got 7% Linux, not 3%”. I don’t think that it was well-made; it relies on disregarding why people don’t call ChromeOS “Linux”.