>Oh? Does that mean artists can post there
i mean that thewaterducts still gets posts from artists, yes.
last post was an uploaded picture of a drawing, from a week ago - it's a japanese board though, so bear that in mind.

>I was thinking them being archives would mean you can't just post there on your own.
besides the wayback links (which you obviously can't post on unless you have a time machine) the others are full-on archives, there is no post function.
they are merely galleries of oekaki from years gone by. (ﾟー｀)
https://oekaki.fuyunoyo.com/ has a registration button and a login field but if it requires verification then that would be pointless.
but you don't need to look that far anyway - the last post on there is from 2013, as i pointed out. it's long dead, so it's a functional archive. surely the owner is still around, or else the domain would have expired a long time ago. i wonder what their motive is for keeping it up. maybe it's sentimental to them? (´ー`)