At the very beginning of the article he dismissed unrealistic expectations, like AI manipulating matter with some quantum magics. Time travel surely counts as such.

And then why bother about AI when Back to the Future reminds us, a sports almanac is all you need. ;-)

Haha. The time travel is part of the thought experiment, just a means to explore an idea. We don't have to actually do it. Let me put it another way. Would you be able to "control the world with tokens" today if you had access to a model 20y more advanced than you have today?