Is there a name for some kind of inverted Kardashev scale, where higher civilizations decide to slow down and go miniature, conserving as much energy and information as possible?
Possibly as a) some kind of bet to hide from other civilizations and b) to delay the heat death as long as possible.
My go-to entry point for exploring those kinds of questions was Isaac Arthur. He goes into the Kardashev scale [1], dying Earth [2], dying stars [3], farming black holes [4], and going past iron stars [5]. A Boltzmann Brain's description bears remarkable similarity to the Judeo-Christian concept of God before time begins, and has been fertile ground for ruminations [6], though none with any verifiable claims backing them in our current knowledge of physics [7].
Now if we could only restructure our implementation of capitalism to be pinned to advancements towards resolving physics questions to survive those kinds of timescales and challenges instead of locked down to a single planet's worth of baryonic matter and cognitive capacity...
Possibly as a) some kind of bet to hide from other civilizations and b) to delay the heat death as long as possible.