Does the Simulation argument "suffer" from the principle of indifference?

According to simulation argument, one of the following statements must be true:
1. The fraction of human-level civilizations that reach a post-human stage is very close to zero
2. The factions of post-human civilizations that are interested in running simulations of their evolutionary history or variations thereof is very close to zero
3. The fraction of all people with our kind of experiences that are living in a simulation is very close to one.

If we apply the principle of indifference to the above statements, the probability that statement 3 is true(You are a simulated being) is a little less than one third. The above argument is structured as a trilemma. Look what happens if we restructure the argument as a dilemma within a dilemma:
A. Post-human civilizations do not come into existence.(50% chance)
B. Post-human civilization do come into existence(50% chance)...If this occurs then (a) Post-human civilizations run simulations or (b) Post-human civilizations do not run simulations.

If we apply the principle of indifference to the restructured argument, there is only a 25% chance (a) is true. It seems to me the principle of indifference cannot be relied upon if it yields different probabilities depending on how the argument is framed. Without being able to rely on the principle of indifference, can one ever argue there is a substantial probability one is living in a simulation?

That's just it. We actually cannot argue for or against Simulation theory. Attempts to do so by Nick Bostrom's critics have come across as short-sighted, and not fully cognizant of the theory's full extent and implications. The theory is fundamentally unfalsifiable.

The best critics and supporters can do, is come up with straw-men articles based on a misused interpretation of Bostrom's theory, or point to recent advances in technology as proof that simulationaism is inevitable, respectively. From the looks of it, the latter hypothesis seems to be winning out. Whether this is due to catering a cultural zeitgeist or actually being self-evident is up to debate.

Ultimately, while I am rather the believer in Simulationism, I am aware that entertaining the idea is intellectual fodder for armchair philosophers, and a metacope for those academics who either espouse, or deny it.

I have been feeling that a physics that is purely local seems to be more and more untenable. If this feeling is common, it might explain why we see people thinking about simulation hypothesis, multiverses, etc.

The simulation hypothesis has always been a silly word game. It goes:

There can be only one real universe, but many fake universes.
Fake universes can be nested inside one another, containing more fake universes.
Given this ratio of one:big number, the odds are very high you live in a fake universe.

Or in other words:
There can be only one real universe, but many hats.
Hats can be nested inside one another, containing more hats.
Given this ratio of one:big number, the odds are very high you live in a hat.

To buy into the simulation hypothesis, you have to ignore the basic information reality that you can't store a big file inside a small file. Even compression has its limits, try zipping a zip file 10 times and see what happens. Odds are much higher a given fish is living in the ocean than in a quart fishbowl dumped on the bottom of the ocean.

It also flies in the face of Occam's razor.

The SH only proves that billionaires aren't the geniuses they think they are, and that the press is willing to believe anything.

String theory posits 11 dimensions. We only observe 4 dimensions. Where are the other dimension? Compacted is what is usually supposed. Why would some be compacted and not others? Well if our reality is a simulation, compacting some dimensions could be a way to reduce computational needs to match available computing power. I think you are correct though, it can't be endless simulations within simulations.