It appears that it has a relatively good idea/concept but a poor execution. A lot of people complaining MC's personality despite training for 100 million years.
@KuroAnsatsu Is it one of those things where he still acts like a wimpy 15 year old despite being millions of years old and presumably a master swordsman due to all the training over that time span? If so then I'll probably just drop this right now and not even bother waiting for another chapter.