Like some others said, I do think that it's true the protagonist isn't as charismatic as Xu Qing, and there's a little less tension because the supernatural elements are mostly kept under wraps.
Even beyond that though, I think that people just prefer when the heroine is the one being teased, and get offended when it's the protagonist being teased by her instead, because they can't see the perspective of the teaser so they tend to view it as more malicious than it really is, and honestly I think a lot of guys are thin skinned when it comes to this kind of thing. It's the opposite of what you usually see in webtoons where the MC is the ruthless witty protagonist with a harem of sycophantic beauties. So I think that may have killed the early momentum, and even later on when the teasing got more even and they delivered that good flashback, they couldn't recover the readers they needed. Well, this is just my speculation. I personally love heroines like this (avatar related).
I'll be happily continuing to read the author's other manhua.