I guess the question boils down to the choice of reference classes, so what makes the reference class “early 21st century humans” so special?
One very speculative reason why it might be worth modeling 21st century humanity is that this century could be a pivotal period in civilizational development. This might be useful because it provides insight into what sort of value systems end up getting “locked in” after this stage of our development concludes.
Roughly speaking, given that the future civilization could determine the distribution of value systems that are eventually optimized by civilizations at our stage of development, they could use this information to predict what type of stuff is being optimized throughout the multiverse. This is helpful because it allows the future civilization to cooperate with other civilizations in the multiverse, which is probably useful if the civilization cares about more than just astronomical waste.
One very speculative reason why it might be worth modeling 21st century humanity is that this century could be a pivotal period in civilizational development. This might be useful because it provides insight into what sort of value systems end up getting “locked in” after this stage of our development concludes.
Roughly speaking, given that the future civilization could determine the distribution of value systems that are eventually optimized by civilizations at our stage of development, they could use this information to predict what type of stuff is being optimized throughout the multiverse. This is helpful because it allows the future civilization to cooperate with other civilizations in the multiverse, which is probably useful if the civilization cares about more than just astronomical waste.