I'd say everything is fair game in love and chyoa likes.
My bunch of disorganized thoughts on this topic:
I too have added these notes to several of my chapters in the story "size matters", and maybe one of those will make it again to the top 10 spot again tomorrow (54 likes at the moment).
So yes it's quite clear to me, that chapters with these kind of notes get an over-proportional amount of likes, that is often not justified compared to other chapters within that same story, and can sometimes easily get twice the amounts of likes compared to the other surrounding chapters in the same branch of the story.
I have to admit, that it feels a little bit like "cheating".
And at the same time i have already felt quite sad and mad, that a simple reminder on a not particularly special chapter, that i have written within a few minutes, can generate more likes than something that is several pages long and where i have worked on for days. Just by putting a little reminder below it. *Facepalm*
But is it really that bad?
I also think that it's just the same with YouTubers. It's pretty standard by now that they ask for likes and subscriptions at the end of their videos. Are they cheating someone? They even might get more advertisement money out of it, because they compete with other channels for the continued attention of the viewers.
So are likes received on these chapters with notes unwarranted?
Is asking to press that "thumbs up" button a bad thing?
Is it unfair to other authors or stories, because it might possibly generate attention to it and the story that is not entirely warranted?
On the topic of "unwarranted" likes. What about a first time author, posting in the currently number one story, listing just a bunch of gaming abilities and generating more likes per chapter than any other author in their position would with their first chapters? ;-)
I don't know. I have no definite answers to these questions.
Another aspect of these appeals for likes: Imho they don't look pretty in the story and disturb the reading flow and immersion.
Has anyone checked, who (what kind of people) actually likes their chapters?
Are they mainly readers or mainly writers?
For me it's mostly readers, and a few writers here and there.