This Brand Reputation Ranking thing has been discussed many times before, and you can also find some articles on AllKPop talking about the opacity and inconsistency of this ranking calculation.
This ranking comes from the Korean Business Research Institute. This is not an academic institution but a commercial company. They have never published the ranking metrics and weighting of their calculation, and outsiders have to pay when they want to know about it.
The ranking is divided into 4 categories: Participation Index, Media Index, Communication Index, Community Index and Recommendation Index. The data of the 4 categories actually come from SNS and social media. NewJeans members do not have personal social media accounts so their scores in this part are very low. But being inactive on social media has absolutely nothing to do with whether a brand will consider using artists to promote its products. Brand management doesn't care about these rankings, and data from their own internal market analysis will surely reflect the real situation more accurately.
Another part of the data comes from fans’ SNS mentions and blog posts. You will, therefore, see some artists with little news and relatively low-key style suddenly ranking high because their fans are more active in posting for the artist and discussing about her/him on SNS. But what does this have to do with the brand’s decision? not at all.
Let's take a look at the August Girl Group Member Brand Reputation Rankings:
Has anyone spotted Jung Eun Ji as the cover girl on the August fashion magazine cover or a large outdoor advertisement in August? Lisa just became a global ambassador of LV but she is ranked 15th, hoho. We've all seen Danielle's (NewJeans) Celine giant outdoor campaign, but she wasn't even in the top 30. The whole ranking is just a laughable farce.
Bunnies do not have to feel bad when you see NewJeans ranked at the bottom on this chart. Only people who don't understand the situation in Korea will be obsessed with this ranking. NewJeans has always been one of the KPOP girl groups with the highest attention among Korean people. Even after spending several hard months living under HYBE's criticism and attacks, things didn't change much.