For you it left mystery, for the people that wanted to progress ahead it left a sour taste of their players getting poached from better guilds cause no one cared to waste hours to getting them attuned.
Game literally changed for this reason and they literally said this a few times to interviews, that attunements were terrible ideas.
Either way, many more people get KSM than people seem to think, but its usually the same people over and over, those that enjoy playing that aspect of WoW, keep coming back, aka the 1% (and by 1% i mean of WoW total population since its start), thats why you see something like 20% KSM taken on dataforazeroth etc.