Yea, it's a bit much, comparable to the "it was all a dream" trope. At times it seems like the writer goes overboard with the perception of the mc. There has only been one person to become his enemy and he is instantly respected by anyone he meets, not to mention he is always stronger than any powerful human that has ever crossed his path. The humans have just been a way for his power to be gauged and many of them have just faded to the background. I think he scaled way too hard. The writer could have truncated the power levels and given the humans more agency and ability. He is practically a god at this point, all of humanity together wouldn't stand a chance against him. Now, he has to win retroactively. It just can't be accepted that he ever lost. The only purpose of this is to make him win and destroy the narrative in the process. It's disappointing.
Was the author having a sentimental self-insertion to try to wash off the killing negativity (aka murder hobo attitude) by going back to save "people" he knows?