To you and all lurkers: I had a similar anxiety at the beginning, because it feels kinda like you're letting complete strangers evaluate your self-worth through the prism of a single comment. So, in my case, I was basically like "If I can't post anything worthwhile then I might as well not post at all," and in that situation, forums turn into like... university Blackboard forums, I guess, where you have to be like "Great comment, X! I particularly enjoyed your comment about how the protagonist of the book symbolizes the ennui inherent to the human experience! If I might add further..." And it feels stilted, and I felt like I had to read a shitload just to bring in knowledge to add to a post or comment or they might yell at me for being wrong and/or stupid and/or not well-read.

But I think this forum strikes a nice middle ground between very intellectual discussions and very casual ones. You can be reading a post about Soviet economics in the immediate post-war period and then the very next post, you're looking at a cat meme. So I would either stick to the more casual discussions (the general megathread is good for this) before you feel ready and not as intimidated by all these people who know all these facts and have read so many books on a subject, or if you want to feel more "productive" online, I would go and read literature and articles etc beforehand, especially stuff that's outside the usual basic reading lists, and then you can become the effortpost Blackboard person (and perhaps from there, move to more casual discussions as you get more comfortable with just shooting the shit).

nowadays I have almost no anxiety on here. There are still definitely comments or posts that I make where I'm like "Oh god, this one's a little controversial, I'm gonna go do something else for a few hours and dread reading the responses," and hell, sometimes I leave comments with no intention to ever read the responses (mostly when the odd lib finds their way in), but nowadays I'd feel totally fine with leaving a shitty joke or uninformed opinion on more casual posts, and you too can get to this point.