This is a poorly written article because it's disorganized and does not advance any line of thought, but I agree with the author's premise that he does not understand the complex topic of freedom.
To me, it seems like a straightforward article and the line of thought is this: One person's "freedom" comes at the expense of someone else's freedom.
Or another way to state is: You're not living by yourself on this planet so "freedom" is not absolute but relative concept because of conflicting relations to others' freedoms.
The middle 5 paragraphs in the article are examples in various domains of the above tradeoffs.
The thesis of the blog article seems very clear to me.
The book was published in 1941, which makes it all the more interesting (also slightly outdated from time to time of course).