if you know the states of all the molecules in a glass of hot water, it is cold in a genuinely thermodynamic sense: you can take electricity out of it and leave behind an ice cube.
Maxwell’s demon, as criticized in your first link, isn’t omniscient. It has to observe incoming particles, and the claim is that this process generates the entropy.
I am not sure this is true as stated. An omniscient Maxwell demon that would only allow hot molecules out runs into a number of problems, and an experimentally constructed Maxwell’s demon works by converting coherent light (low entropy) into incoherent (high entropy).
Maxwell’s demon, as criticized in your first link, isn’t omniscient. It has to observe incoming particles, and the claim is that this process generates the entropy.