If you go on to the next paragraph in the wikipedia article you copy-pasted without citation, you'll see "The term "efficient" is very much confused and misused with the term "effective". In general, efficiency is a measurable concept, quantitatively determined by the ratio of output to input. "Effectiveness", is a relatively vague, non-quantitative concept, mainly concerned with achieving objectives."
Comparatively high cost is the main factor why it is still be considered less efficient although that is slowly changing.