I feel you, but also most of the time the author writes the stuff in novel form, it gets well received enough to get adapted to webtoon and the publishing company picks the artist to do it. I find it hard to imagine that someone who cares for the verisimilitude of their fictional world would just ignore the argument you made, tho i guess there are also a lot who don't
Three things you mentioned here: first I got a bit annoyed with the possessiveness, but I was expecting the moment they solve it. Second, when they tried to solve it, suddenly a wild PAST MOMENT appeared and got annoyed again... And now you reminded me she is a stick with a sword but still super strong.
Well, we can interpret it as she is super skilled, not like super strong (like more of the agility type) but I guess the translation or the meaning they want to convey doesn't match.
Still it's fantasy soo... She looks super thin divine and she has no muscles.

The ml’s possessiveness is annoying but also I’m sick of these authors making these female knights so frail like how is she defeating these buff ass men w her frame??? There’s no world where she actually overpowers these guys or even the monsters like make her buff damn! She’ll still look pretty I promise