Holographic universe theory has indeed been around for a long time, and there are different definitions of what exactly constitutes a simulation or reality, so to speak. Ancient texts specifically mentioned the seemingly ethereal nature of the world we live in, with many references to "other dimensions" as being accessible through meditation and and even the use of psychedelics.

All of these are personal experiences being shared through language, a flawed means of communication. Hence the grave misunderstandings that we see everyday associated with the word "god" or "religion."

I believe we can observe patterns repeating through the different magnitudes of scale that we can observe reality through.
For example, we see the same spirals that form certain galaxies, in relatively tiny objects such as seashells. There is interconnectedness all around us.

With that being said, the matrix allegory i think specifically refers to the idea that reality is not at all what it seems and that many people are in a "slumber" of sorts.

For those who have woken up, they would describe their former existence similar to being "in another dimension". All very subjective terms. But when you can juxtapose many different states of consciousness, and analyse them relative to each other like this:

Sobriety - dreaming - intoxication - hallucinations (from sickness or from drugs) - meditation - the "zone" or "it"

There are even more to add, but the point i'm trying to make is that even during everyday life, we transition through different phases of consciousness. This in turn means that our definition of reality is constantly in flux. If you then apply the logic that if we are in control of our consciousness, we can essentially do anything we put our minds to, this becomes similar to the idea of being in a video game.

The path to truth is not a straight line. It is a spiral where you return to previous points with a deeper understanding of truth.