I think reddit’s staunch hatred for artists is pretty gross personally, I’m very much in favor of letting artists advertise in the manners outlined in the op.
Once post tags/flairs are implemented it’ll be easy enough for folks who aren’t interested in character art filter it out, and people who are, to actively search for it.
Art is, now, a pretty ingrained part of the DnD/TTRPG culture and I think we should celebrate or at the very least, aide in the self-supporting of the people who create it.