Relatable... I've been in this situation for a long time
I'd suggest to try joining conversations regardless. I know it's easier said than done, but I think it's still worth at least trying. I've been in a server and I've said something every now and then... then a bit more often... eventually I did take part in a conversation... after a while again... and again... all of this took months and I still struggle with anxiety but along the way I made a few friends in that server. And I too didn't think I would be able to actually do it