@tnt261
What is a god?
That's a good question and you provide several elements of answer.
But the main point is that there have been multiple definitions and ideas of gods throughout history. The Christian God is a rare example of "perfect god" (very debatable though), where examples of "more human gods" are numerous (basically, super powerful and often immortal beings, with the same kind of intellect and emotions as humans).
The two most common traits are immortality (in terms of lifespan; some gods can be killed) and very powerful magic powers (from creating things out of nothing, to curses, to controlling some aspect of the world). Often anthropomorphic, but that is not a very large majority.
There are even myths of humans ascending to godhood.
Setting aside the fact that gods are fictional, they are not necessarily bound by faith either. This part is only used in the context of organized religion, where you need to believe blindly when there is no evidence that gods even exist. Faith is a matter of accepting and following a god that never interacts with you directly. So this is essential to the definition of god.
By this definition, the MC here can fit the bill.
Not the "absolute god" type that christians profess their god is, but the more general definition.
Assuming he would not age and die of natural causes, he is now a powerful immortal being that brought and mostly controls a whole new concept to this world: "status" as something measurable. And he has vastly superior control over "divine power"than the mortals around him. (Some of whom have pretty high divine power themselves by now.)
If you're not stuck to the idea of "capital-G God", three is no problem at all here.
Also of note, in Japan, the definition of god is way broader and nuanced, and they have several words that we can only translate into this same word "god" because we lack those nuances. I'm curious what exact word was originally used here.