There are a few who were disappointed for the exact same reason you described here. The vast majority wasn't though and i do belong to this majority. I have my own points of disappointment with it, on a very subjective level.. you can tell by my signature
![Wink ;) ;)](data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7)
, but lets be fair. Linda's progression wasn't just a "slight" one and Caroline's either, i assume the lewds is what you were referring to and it was made crystal clear that Linda Caroline are gonna be the ones who get an update. The twins were something unexpected and thus extra.
So content wise one has to look through the lens of Linda and Caroline only. And yet Sarah and the twins got content too. I say the twins were pointless, the already established girls could have received content instead... but oh well.