Furry Chat

Simple: if what you want is to try to get eyeballs on your art, you're not going to post it on a website that restricts its visibility. I'm never going to see that much content beyond my own instance. I need to follow the artists individually to see their art, or they need to be somehow connected to someone on my instance.

That's the ultimate non-starter, and Twitter doesn't have that problem.

But also, Twitter has always been an awful place to post art (and by extension, Twitter clones). You have to continually scroll through newer posts to find older ones, it doesn't have nearly any of the features that websites made specifically for posting art have, and the tagging system is broken.

What you're asking is, "Why aren't people posting art on a website where each individual post is treated as disposable, as something to be seen for a short while before being buried by newer posts?"

What I'm asking you is, "Why would anyone do that if they had any other choice?" It has all of the drawbacks of Twitter's website design with none of the benefits, and it does some things even worse than Twitter.

Aside from all of that, right now, artists feel like Twitter is where their audience is and the only reliable source of commissions. They're not going to move until that changes.