We see in Tamara Davis's Fig 5.1 that the 2D horizon entropy of our observer universe is bounded asymptotically by a constant value ~ 10^123 BITs.

This is actually the upper bound of the thermodynamic entropy of all quantum fields in the interior 3D bulk that are merely retro-causal hologram image projections in this crazy theory that 't Hooft invented in 1993, perhaps not realizing how crazy it really is - is it crazy enough to be true?
Therefore, as clock time progresses for the ideal immortal observer (central world line in Fig 1.1) there is an effective cold death of sorts since the entropy cannot increase indefinitely. Or, alternatively, if intelligence requires negative entropy, then everything must become reversible in the far future so that every act of consciousness there is balanced by an equal increase in entropy without any irreversibility. This seems odd.
Of course matter flows beyond the event horizon, which would normally increase the area of it like matter in-falling into a black hole. Actually to us inside the horizon the in-falling matter is nonlocally smeared all over the horizon. The only way this can happen consistently is for compensating negative entropy in the bulk - looks like perhaps the creation of Tielhard de Chardin's cosmic VALIS cosmic conscious intelligence?
Remember, I said the theory is crazy. I am just beginning to see how crazy it really is. ;-)