[brudgers]

The hurdle is inconvenience. Using a special news reading app and maintaining an account are inconvenient relative to just reading for free. On top of that, reading an article becomes a decision of both time [to read it] and money [the price of the article], that's also [mentally] less convenient.

To me, the difficulty is that there is no obvious win for the pay by article model and my experience is that people hate being nickeled and dimed. Charging is not necessarily the best route to build the goodwill necessary for donated effort toward curation and curation that relies on goodwill tends to attract players with financial motivations in addition to people with voluntarism in their hearts.