Wow, so much of that is wrong
Goetia's goal was to press the reset button and make a world without suffering by becoming God,
Nope, he was just going recreate Humanity as he wanted us to with 'no suffering' as the primary goal, but a lot of other stuff was going to happen, he also didn't need to change any to do that, he just needed to wipe out the existing Humanity first.
since he already was a second class planetary entity he even had a decent shot at it.
He is a Gestalt of 72 Demon Pillars that collectively decided to act like how they thought Solomon would act, leading to FGO, he was going to succeed but Chaldeas stopped him
True Magic isn't as bullshit as it first appears after FGO, so the Entities are advanced enough that their powers could fight a Colony like Goetia so self-preservation of predators won the day.
On the contrary, True Magic is exactly as bullshit as it appears, the problem is that the enemies have equivalent bullshit. Zelretch can just decide which timeline is real, Aoko accelerated the heat death of the universe, but True Magic is and always has been defined by the limitations of Humanities ability.
To begin with Earth isn't that closed of a system we are leed to believe by the magus community's close mindedness,
It is effectively a closed system so long as nothing comes in from the outside, just because there isn't really anything keeping shit out, doesn't mean it isn't a closed system.
almost all gods were "adults" invited from the outside to take the role of administrators, so the existence of planetary predators like the entities isn't that surprising when we take into account The Umbral Star "worker bee" soloed the Age of Gods.
From what I remember, Sefar was sent by the Velber specifically to cull the the gods, also it only started the decline of the Age of the Gods, other things happened that did more to end it.
Hell, humans(A-rays and Liners) of Notes even evolved into Viltrumite-like beings that treatened the Planets enough that they so did a preemptive strike to stop them from colonizing the stars!
That in completely untrue. Notes was caused by the TYPES responding the Gaia's request to come over and eradicate Humanity because Gaia saw that they would continue to live on it's corpse when Gaia died. This is roughly equivalent to the microbes in your stomach gaining sentience and growing a thriving civilization on your corpse. So, Notes happened
explicitly because Humanity didn't colonize the stars, if we had left Earth when Gaia died, non of the TYPES would have done anything, it's only because we continued to live on Gaia's corpse that they tried to kill us, because we were the equivalent of a zombie horror movie. Also, no the A-rays and Ether Liners of Notes weren't anywhere near as badass as Viltrumites, only Gun God and Ado Edem could meaningfully affect the TYPES, the rest could barely slow them down.
The idea that humans and entities relationship will evolve into a long term partnership of symbiosis isn't farfetched when we look at Eidolon,
What dies Eidolon have to do with anything? Zion was going to destroy Earth as a whole across every timeline, it didn't care about Humanity at all, Humanity doesn't really have anything to offer Zion that it wants. In a partnership or symbiosis, both sides get something from the relationship, what are the Entities supposed to get from us?
dead apostles are basically honorary fairies of Big Red,
Dead Apostles
are faeries, which means they count as part of
Gaia, who the fuck is this 'Big Red', the only one I can think of is from DxD.
for all we know this is thursday in Galaxy scale of events and the Entities themselves are small fry compared to whatever extinguished the civilization that created the Greek Machine-Gods ruled by the dysonsphere Chaos.
Earth is only planetary level in a whole ass Galaxy, news at eleven. The Velber wiped out the race that created the terraforming ships that became the Machine Gods. You'll note the also destroyed the Machine Gods.