I'm not sure why links to your channel wouldn't work, unless iOS users aren't aware that they need to enable NSFW content on their devices via the web interface. Seems to work fine for me, and imho a Telegram Channel is better for one-way communication (like announcements/postings) than any part of Discord is.

I use discord for years and never heard about problems for fetishes or nsfw stuff, and I've seen that kind of stuff posted there!

Honestly compared to instagram, discord quality is great even without paying

I can't compare it to telegram tho as I never used it

As long as you mark the server NSFW and the channels where fetish content is posted as NSFW, you should be fine on Discord. Can always use it as an intermediary location too, and help people join the Telegram channel(s) from there if needed!

So long as you mark Channels as NSFW They wont care too much but be sure too have a good mod too keep the peace
Like Vore is marked as NSFW
Also Recommend that only have 18+

I follow too many artists to keep up with where you post. I personally prefer FA as a viewer, but for talking, discord is nice.

The only hard nos on Discord are mark channels NSFW, no under age content, no real life depictions of violence/harm/etc, NSFW servers should be 18+ only. You can make a Discord that only has channels you can post to as well so that it requires less moderation. Posts to say your open for commissions page regardless of where it is. As well as currently completed work.

As for quality of images it's no different than FA though base line has an upload limit though I've only hit that myself when trying to post really large projects. For previews or general consumption it's fine. If you want to make high quality content available there's probably upload sites for files that are better of a service than most social media platforms.

As for alternatives to post a lot of artists are using Twitter more and more, it's apparently easy for them to upload and manage content. Though on the consumer side of things it's hard to search for images posted as Twitter doesn't really have much in the way of a tagging system.

wow, such clear information, you seem to understand very well the situation with social media. If I have any questions, can I contact you in discord? :0

I know some but not all. I'd be happy to answer questions if I have the knowledge.