I think this type of ending is just more common in East Asian media in general, I've watched plenty of Korean and Japanese shows and movies where it's left on a more open-end. I'm not saying you have to like it, more that there's a reason for it other than to be annoying.

I think with Chinese shows because they're so heavily aware of the fandoms around them they have a habit of doing more open-ended stories so that the fans can do what they want in fanfic/art, and in the case of the paywall episodes that sadly tends to come about from having to curtail to censorship. Which isn't great but I'm forgiving of that since I know that they'd likely have that ending in the main release were they able to do so, they just want to be able to actually air what they made.