The author doesn't even have a position. They're just summarizing a book that someone else wrote. It's not even a book review. There's very little supporting evidence given, and even worse there is no discussion of why the book's ideas might be wrong.
The click-bait title did draw me in to read it though, so I guess whoever wrote it did their job.
The piece (titled "Liberalism is loneliness") seems to agree with the thesis of the book (titled "Why liberalism failed"). The place for supporting evidence is thus surely in the book itself, rather than the article, no?
(I can't tell if it agrees with the ideas of the book, because, as you say, they aren't clearly indicated—but I don't see any reason to think that it doesn't agree with them. In fact, it's hard for me to see how the piece could be both a mere summary of a book and in disagreement with that book. Or are you saying that it should have offered a balancing perspective by discussing possible issues anyway?—that is a reasonable, but, I think, not obligatory, approach.)
Anyway, I didn't find the piece life changing, but it was an effective way to get me interested in the book referenced (perhaps just because I am currently listening to an audiobook of Nicholas Shorto's "Amsterdam: A history of the world's most liberal city", which similarly explores the subtle shades of meaning in the words 'liberal' and 'liberalism' and their derivatives); so maybe it's not all bad!