Itzy has a great start. Dalla Dalla was very popular and Wannabe was also very well received. But, they are not consistent and that is very important to maintain their position on the top especially with this fierce competition in gg landscape. I don't know what happened with ITZY but their music is getting more noisy and "disorganized" now. They don't make sense but the group is just so popular that probably many are not ready for this conversation.
Nmixx on the other hand, didn't even have a great debut. To be honest, they're the weakest new gg that debuted under big company. Twice didn't have impactful debut too but not this bad. People will say that at least they're doing great in sales. Well, tbh nothing impressive as that's the privileged for a group under big companies especially in this generation. What is more impressive is how they can sell that much with this quality they have given.
Itzy and Nmixx are good group and I can't blame them for their producers and company decisions. JYP is big 3 and well known for their iconic gg. Twice discography for example are very good and I don't know how they are doing from this to whatever they give to their new gg now.
The real question is, what is Jype actually trying to do? I think they should understand by now that they're not that good at doing experimental music or whatever they're doing now.