It is a weird move. This isekai is sorta different from the other revenge villainess isekais in that she's noticeably pettier than the girl who killed her.
Like, almost immaturely petty.
Either it's a good plot device to build up her bad karma and set her two steps back...or the author likes being petty for no dang reason. Would be disappointing if it's the latter, but as a fellow petty toxic person, I totally get it and would love to do the same. The author and artist are just drawing the stuff something that readers could relate to.
Thanks for the chapters!