It's... difficult to describe how exactly I've felt on this site. I've certainly felt the same fear-ridden anxiety prevent me from commenting, from chatting, that prevents me from sending messages in other spaces. I've also felt that I've made others feel heard, or that I've been heard through the posts I write, I don't think SaSu is dissimilar from other social media sites in this regard just because we're allowed to actually talk about the subject without fear of being reported for it.
I don't know what effect SaSu has had on my mental health, whether it's helped or hindered. I've found myself slowly getting better, but that feels because of internalized debates with myself. I will say that this site has provided any number of resources and recommendations (books, music, other media) that helped me with the inner struggle. I find it hard to know whether I would've come to my current perception of life if it hadn't been for SaSu being here, providing an open space for such discussion.
Overall, as to whether this place has a positive effect on the people who visit it, I can't say. But I don't think it's some mystically evil existence that causes people to take their lives. The people that hate sites like these point at it and make that claim, but the bigger problem is society falling around us spurred on by the exact rhetoric they use to try and censor this website, not that the website exists. If anything, the existence of this website is evidence of their failure to make life bearable, trying to take it down while refusing to fix the more significant issue does nothing to help. It only kicks the can down the road, as they've been doing for years.