That's a bad way of describing the problem, because it's not just "microtransactions" that are affected, and the result is not making them "uneconomical" - it's making them impossible.

An effective block size limit doesn't mean that some transactions get more expensive - it means all the transactions which are allowd to be process become more expensive and the rest are prohibited entirely (right up until Bitcoin becomes so completely unfit for purpose that it's abandoned entirely)