Also i think its because Bertia Character is just so endearing & different. As someone who got isekai’d as a Villainess She doesn’t try to change the course of her actions to save herself nor to live as she wants like any other manga/manhwa. she actively trying to be a proper villainess, it just that she’s way too pure for it.It's also one of the first, in terms of major popularity. It and Bakarina were getting fan translated at around the same time.
As has been argued in earlier comment threads, Bertia has had the better staying power because of this dynamic.