Unfortunately the author somehow missed that "unifying the Linux desktop" is not the goal of Portland.
I guess I don't have to point out that neither of the latter two project has "unifying the Linux desktop" as its goal either.
Now the question is, why did the author think that Portland aims at this unreachable goal?
Is it some bad wording on the website? Some ambiguity in a press release?
Obviously any project where contributors of different free desktop teams work together will result in some kind of common good, be it a specification or a shared implementation.