Something I've noticed is that they tend to be very new, with few chapters released, POV one-page-a-chapter etc. they also tend to have more romcoms and isekais.
The popular new titles have new manga entries from the last 30 days, and is largely based on follower count. However newly released chapters affects it a bit, like today you could see that the 10th place got switched out even though it had less followers because of a new chapter.
I don't think they're going to do much about it, as RogueKitsune said they're going to go back to using view count for recommending titles, and it's just a placeholder. Apparently they already have view count in place, and you can see it on the manga pages, but they haven't made this information public yet.
From what I've gathered from earlier discussions this is probably one of the features they're working on implementing soon, so I wouldn't think it'd take a long time until it's here. There's been a lot of people complaining about the "popular new titles" already as they don't feel that they're relevant to them, and also because a lot of one shots and twitter shorts fill it up all the time, which is fairly useless in my opinion.