That's not how I see it since the strongest techniques he got so far are from Buddha and son wu kong ... and technically speaking so far no og gods (og as in fully or from the start gods like full on born gods such as Odin and Zeus, ye Odin is "technically" a titan but mythology logic says na he a titan god but moving on(￣∇￣")) just transcendental beings weather they are humans, half humans, or other creatures I guess (for example Atlas is a Titan but debatable depending on what legend you read) who later on "some" transcended to godhood/directly serving gods in their legends.
Author is being smart in choosing people who did not start as gods from every mythology and I guess Norse and Greek mythology have a lot of those. ╮(￣▽￣)╭
some have different telling's that say og god but the way I see it as long it's "debatable" it's valid but that's just my opinion so feel free to see it however you like. (=・ω・=)
True most mythologies usually r those who already r born gods but im sure there r some mythologies outside Norse & greek where some r not born gods & were og human
The author must really like the greek gods huh??