I think the article downplays the element that the attack probably achieved its goal which was not to actually hit something at Diego Garcia, but to show that thing 2500 miles from Iran are potentially targetable by Iran. That starts conversations like the one here and in other fora about whether or not Iran would limit themselves to military targets (Russia doesn't as an example) and if not how could Europe and its East Asian allies protect literally everything with their finite supply of defensive units.