The deposit thing looks insane to me too. My rental deposit is held in escrow by some third party; I've never heard of anyone not getting their deposit back when they move (unless they did something to deserve it e.g. trashing the place). The only issue around deposits is that you usually have to pay a deposit for the new place before you've received the deposit back for the old place, which can cause cashflow issues.
I've always thought of the U.S. as a great place to be rich, but a terrible place to be poor.
On the other hand, I find it laughable that this author describes a 900sqft apartment as "very small". 900sqft would be considered a decent-sized, mid-range apartment in London, and if you're poor you'll live somewhere MUCH smaller. Americans have such ginormous houses, even the poor ones.