alt Hacker NewsOLPC may not have helped many rural children directly, but it did inspire an entire class of computers (netbooks/chromebooks) that made computing more accessible for children and adults across the world. For that reason, I think it was a worthwhile pursuit.
Netbooks were largely a passing fad as were Chromebooks in large part, though the latter are still around to some degree. However, OLPC went beyond cheap laptops and, however well-intentioned, never really took off as a unique entity.