However, the holographic universe concept is not really implying it is a simulation...

Relating to the 'simulation' concept, it is fascinating that 'information' is popping up as an important quantity in more and more areas of cutting edge theoretical physics...

There is a a VAST amount of theoretical work on what happens to the information that falls into a black hole...
http://www.pbs.org/wgbh/nova/blogs/physics/2013/12/do-black-holes-destroy-information/
And a new theory of gravity that I find very satisfying (Disclaimer: I dont have the background to evaluate this theory's merits) relies on the INFORMATION contained in a volume, and as a result removes the need for dark matter:

https://phys.org/news/2016-11-theory-gravity-dark.html

In 2010, Erik Verlinde surprised the world with a completely new theory of gravity. According to Verlinde, gravity is not a fundamental force of nature, but an emergent phenomenon. In the same way that temperature arises from the movement of microscopic particles, gravity emerges from the changes of fundamental bits of information, stored in the very structure of spacetime.

My unqualified opinion is that this theory is one that could revolutionize physics...
https://phys.org/news/2016-12-verlinde-theory-gravity.html

A team led by astronomer Margot Brouwer (Leiden Observatory, The Netherlands) has tested the new theory of theoretical physicist Erik Verlinde (University of Amsterdam) for the first time through the lensing effect of gravity. Brouwer and her team measured the distribution of gravity around more than 33,000 galaxies to put Verlinde's prediction to the test. She concludes that Verlinde's theory agrees well with the measured gravity distribution. The results have been accepted for publication in the British journal Monthly Notices of the Royal Astronomical Society.

The concept of information seems bound up in the very nature of space-time... almost like the universe is a giant information ... processor?