(Apologies in advance for the wall of text but I don't really have the brain power to try and make this more concise right now.)
I think there's some weight to this. I was thinking about this the other night when I was reading over one of your other threads, but I think it is potentially correct to consider the dynamics of at least the primary characters (maybe even just the Alicorn/Deitiy characters) of the show as a spiritual/religious canon or mythology (the other characters very well may represent the perspective of the human experience within this framework).
I know that religion isn't really supposed to be discussed outside of the debate pit but I don't think I can really answer the question without at least partially doing so. (mods feel free to delete this reply if it breaks site guidelines)
One way you can think about religious and spiritual mythologies is as a metaphorical description of the structure of the phenomenology of human experience. Take the Roman Pantheon for example, each deity can be seen to represent a different aspect of reality as experienced from the perspective of humanity (or any given human), and the mythological stories told about the dynamics and interactions of these deities can be seen as metaphorical descriptions of how these aspects interact with each other to create the reality we experience, and I think the same can be at least partly said about MLPFiM.
It's been a long time since I've watched the show so I can't give a lot of examples here, but a big one that comes to mind which also fits the theme of this thread is the dynamic between Luna and Celestia. There's a myth which permeates many different religious and spiritual systems that describes the dynamics of what we consider to be good and evil (which in this context can also be described as what we consider to be of benefit to the project of perfected reality vs what we consider to be of determent to the project of perfected reality).
In short, the myth essentially tells the story of how 'evil' is the manifestation of the dynamics of unaligned and uncontrolled aspects of reality which, in there unaligned state, cause destruction and chaos. These aspects however, if aligned properly, can be integrated and used in pursuit of what we consider to be good (one example of this is how uncontrolled aggression can be devastating, but when integrated and controlled correctly, this aggression can instead be channeled as assertiveness in the pursuit of good.)
I think there is a case to be made that the dynamic of Luna and Celestia is a retelling of this myth (I think there dynamic is also used to retell other myths but that's outside the scope of this example). Think of S2 E4 (Lunar Eclipsed) where, to paraphrase, Nightmare Moon becomes Princess Luna. Nightmare Moon can be considered to represent the manifestation of the unaligned aspects of reality which, in there current form, cause chaos and destruction (later on the character Discord appears to represent chaos more generally but that's not really what I'm talking about here).
In this episode, to quote the MLP wiki, "Twilight Sparkle helps Princess Luna change her frightening demeanor and become accepted by the other ponies.". To use the terminology I described above, Twilight helps the unaligned and destructive Nightmare Moon, who to the ponies at this point is considered an evil character, align and integrate with the 'good' reality of the ponies transforming her into the 'good' character Princess Luna, who still embodies the same aspects as she did before, but now they have been properly integrated and she is able to become a force which works with in line with the good. (For those familiar with Jungian Psychodynamics this Myth can be described as the integration of the shadow)
This isn't something that is exclusive to MLP. In fact, a large amount of popular media is contemporary retelling of myths. The Harry Potter series is a metaphorical archetypal mythology for example. I believe Rowling even said this herself.
I apologies if some of the terminology I used here is confusing. I couldn't think of better words to use off the top of my head. But if you have any questions feel free to DM me and I can try to better clarify what I mean. I also don't claim to be 100% correct in what I say, this is all just based off my own understanding and interpretation.
I also imagine there are people on the forums who will have great arguments to debate what I've tried to explain here but this thread is not the place for that discourse.