It's just a random thought but I think individual member's popularity plays a lot more in charting than we thought
When ITZY first debut there was a lot of hype for the new members I remember.
But not sure what happened but after Not Shy and Mafia it seems like their charting wasn't as good.
Remember the most recent song that charted high? It was Sneakers. And coincidentally remember who went viral during that era?
This video got a lot of views and hyped Chaeryeong way more than she was before and more and more people started checking on her and ITZY out which I think might have also affected Sneakers charting way more than what we thought
But comebacks after, there wasn't any like viral moments of any members.
JYPE's fear of his groups having a "Suzy" might have been his biggest downfall that he is subconsciously (or maybe purposely) restricting the growth of individual member's popularity because he is afraid they will outshine the group, but that reason might be the reason why his GGs recently weren't able to reach the charting heights they once had.
IVE we know they have 2 powerhouses of Wonyoung and Yujin. The other 4 members obviously aren't on the same level of popularity and if Wonyoung/Yujin weren't in the group I doubt IVE would be able to do so well. This is not saying the other members are unknown because they are actually doing fairly well but we know the gap is huge not just between those 2 and the other 4 members, but also between them and the rest of the industry.
LSFM I feel is a group where all members are pretty known. The recent Google search results reflected that a bit, with Sakura being the only 4th gen member in top 10 most searched GG idols and the whole group is in top 50.
aespa has Karina and Winter. Karina is really really popular, maybe only after Wonyoung/Yujin in Korea. Her Instagram followers are no joke.
New Jeans members are all pretty known as well. I don't follow the group ad closely but I see members being brands ambassador and stuff.
I also don't follow NMIXX that closely but somehow I feel Haewon is also everywhere. I see her on shows and MC gigs.
I don't exactly see the same happening to ITZY. I MIGHT BE WRONG ABOUT THIS, but just based on memory ITZY seemed more focused on touring and stuff now in their later years and didn't really spend the time to build their individual popularity. They don't go on shows, they don't have as mu u solo gigs from what I remember. They don't even have personal Instagram of which many of the above stated groups have.
Maybe it's also the music, because groups like StayC don't exactly have that big of a fanbase but Bubble and Teddy Bear did so well for a non Big 4 group. So well might be an understatement they actually did amazing.
But yeah I feel the member's individual name is one of the key reasons as to why they aren't charting as high as they used to. Because they released songs like Loco which were more reminiscent of the Dalla Dalla/Wannabe sound but that didn't do well and of all songs that did well it's freaking Sneakers where Chaeryeong had a viral moment