The problem with micropayments isn't the tech really, it's that only the users want them but not any publisher. Which is completely reasonable.
Edit: Typo
As a publisher, I'd want consistent subscription revenue. The goal is to convince users to pay after they hit the paywall several times.
If you are a publisher, something which gains widespread attention might happen in your region, or an article might become viral for other reasons. You know that a lot of people would like to read that article and not become subscribers. So if you can sell access to an article 50 000 times for 1 dollar, that's $50 000 in income you wouldn't otherwise have.
But unfortunately, very few people are willing to pay a dollar or 50c for an article which they are desperate to read.