This isn't true. Yes, it's only checked locally, but you can store the key-code used and if you connect to another player with the same keycode it can prevent you from playing together. This is something many companies did to their games. But many others didn't, and they were treasured for LAN parties.
You're confusing the impact of the decision with the prevalence of belief in it. While that may objectively be the best way to combat climate change, it doesn't imply anything about how many people are making that decision for that reason.
The author completely missed the part where Lain became a god... Or how she erased herself from time and space because she could no longer relate to her friends and family. It reminds me more of Welcome to the NHK than Evangelion, honestly.
"Private tutors" can be anything from an after-school karate class to visiting a piano teacher's house for an hour of instruction. It doesn't have to be solely for elite people.
It also encourages slavery. Who sows your clothes? Who assembles your phone? Who picks the vegetables you eat? Really it's all the same person: The cheapest option.
Indeed, if slavery turned out to be more efficient, it would.
But I think that the claim that slavery is more efficient does not hold, since opressing people binds a lot of ressources; also opressed people tend to do work as minimally as possible.
So it is much more efficient to give people the illusion of freedom instead of enslaving them.
Also it doesn't imply it'll use the least amount of resources, it implies it'll use the least amount of _money_, which means the cost will be exported to countries that can't afford to say no... Are we really surprised at the amount of slave labor in the world?