Probably because they signed up for a month only and then they all stopped.
Still we must be thankful to all of them for uploading so many edits from Burgerkiss.
So it's better to wait till we get a new uploader, and as TheBurgerKisser (one of the uploaders) said: "I do this to better the galleries, not to hang out art".
Kuroso is correct. Imagine if many people banded together. Like a discord or a group chat. 10 people contributing $1 a month, and then voila, constant uploading.