Because it goes against literally every isekai trope. The MC isn’t an OP hero with a cheat skill, their past ‘gamer’ knowledge is useless. They have been given the shortest end of the stick by being a short orphan girl. It’s like Tanya the evil but where the roles are reverse because in reality...
You will be disappointed , in 10 chapters the ML (probably be a blonde prince of black haired duke) will appear become ‘interested’ in the FL snort her hair like cocaine and will basically demand she never do anything badass
10 bucks she never picks up a sword, and doesn’t use her prior world skills and spends more time getting her hair sniffed like crack cocaine by the MLs along with wearing dresses and eating cat/tea
Wow that armour that actually looks realistic and protective, not like usual dumb isekai armour that doesn’t even protect the stomach in that silly V shape