To me it's kinda the opposite, it's more or less saying - 'Everything Jadis is saying is true . . . and also all of it is also completely and absolutely useless no matter how true it is.'
Which makes sense when you realize that Jadis already had a mindset of supreme passivity. So of course, even with omniscience, that's all she can see herself doing. She was literally telling herself that she was finally in control of her life as she switched on the machine . . . the machine that had been raised and told switching on was the only purpose in her life . . .
It's literally a person who knows that they could do better, and be happier, using any excuse they can to do nothing. Because doing things is hard.
Or, alternative, all of the effective altruist cunts who want people to ride their dicks as moral paragons for being rich by dressing it up in lengthy essays of empty solipsism.