I’ll try my best.
Change in a way is demonstrable enough in the fact that we know it happens. For example, everything is moving. The Earth is moving around the Sun. The Sun is moving around the Sagittarius A* black hole. And in fact there is no absolute zero in our Universe. No absolute zero means everything is vibrating as demonstrated by string theory. And if everything is vibrating, it is changing, no matter how slow or inconsequential it may be.
On the other hand, there may be Universes where there is no change. If change is God than no change means there is no God. And a Universe that can’t change can’t possibly have a cause or an effect.
Concepts are abstract enough to be universally applied much of the time. Some concepts are abstract enough to not really mean anything. Beings however are are usually subjugated to a finite point. Zeus was worshipped; now he isn’t. He is not accredited towards the change of many things anymore. The same will happen with Yahweh. If Yahweh wasn’t accredited towards the change he applied on Earth - which I would argue he didn’t even do - then nobody would worship him.
On the other hand, the concept of change and what causes it is so universal that nobody can deny it. Find me a language which change isn’t in their dictionaries. It’s impossible. Change is elusive sometimes, yes, and we don’t fully understand it currently, but we know it so well already that it is impossible to deny.
Dasein, presence, or what I would argue the seeking of patterns will always be an issue. A cloud could look like Mickey Mouse. Is the cloud Mickey Mouse? No. Does Mickey Mouse exist? No. Yet some people may look at that cloud and identify it as such. Will the cloud change and become new images to the people who see them? Of course. Mickey Mouse changes, but ironically enough change does not change.
Well, if change is God, and not all changes are positive, it makes a strong argument that change itself causes evil too. Evil could be analyzed differently to various people too, and what a positive or negative change would look like could be entirely subjective.
As far as conceptions and definitions of God, Earthseed doesn’t offer the kind of bullshit that we see other religions. It’s simple. Earthseed states that change is God; syntheism is the theology of Earthseed, and while Earthseed is a fictional religion it doesn’t mean it’s a fictional idea, and there’s been to my knowledge four real religions that have existed under the umbrella of Earthseed. Terasem, Exaltism, Turing Church and Astronism. If you were to call me any of the first three I would agree with your assessment in fact. All four are Earthseed but touch and develop their basis on different patterns in the transhumanist and futurist tree. Terasem is straight transhumanist; Exaltism is focused on extropianism; Turing Church is cosmist; And Astronism is astrological. And out of the four I would argue that Terasem has the most ability to change the future, even if the question of the religion’s future is already at stake.