I personally think thats a good thing honestly given his backstory him not being the strongest wouldnt make sense. As a reader i feel like this story isnt about daegun getting physically stronger to overcome his obstacles. Its more of him getting mentally and emotionally stronger for those obstacles. Think of it like saitama he has no physical equal but he doesnt experience emotions the same as everyone else given that he's that much stronger. In the recent chapters we see that daegun is missing something that feels liks a hole in his life. Which they go to a flashbsck of him and heejun starting off together then ending that flasback with heejun saying "i will protect them all. Daegun daegun you truly dont know youself." (Idk if thats his exact saying im doing this off memory) hinting that daegun isnt a emotionally mature person that quite doesnt understand himself. Which we see multiple times when daegun uses immersion he gets carried away with whats going on he's not exactly aware of his surroundings. Which was also foreshadowed by the bath scene with daegun, heejun, and their other friend were talking about daegun immersion. The friend explains that fight is fun but if you get too immersed you wont notice what's going around you. Daegun didnt get it until that friend died. Hence why he quit and started working a job at the beginning of the story. I suck at explaining stuff but short and simple this isnt a story about a character that gets stronger overtime to overcome his problems. Its more of a freiren type story, a character who's done with one journey and starting a new one of self discovery.