I agree with the idea of removing outright insults, but I also think studios' decisions should be moderated. They might just delete anything negative, so maybe they could flag a comment they want removed and let SLR mods decide. For example, a comment like, "The filming is very unprofessional; bad angles, camera feels like it's on the stunt cock's belly, gives giraffe neck vibes, no structure in the positions, amateur storylines, poor eye contact like she's looking at someone behind the camera, and the scenes are way too short compared to the standard 45 minutes," shouldn't be removed. However, I believe most studios would get rid of such comments if they had the power.
I always check comments before watching a scene, and if someone flags any of these issues, it might make me reconsider watching. The current rating system on SLR isn't very helpful since we only have a "Like" button. People don't only decide based on popularity and the number of likes, on whether to watch a scene or not, so comments, especially negative ones, are very important
When it comes to what you consider insults, I don't think saying things like "I hate plastic looks," "Older women are ugly" or "This girl isn't attractive", should count as insults. This is a porn forum, and we're here to rate models' bodies based on our tastes. We're the consumers, and we have a right to give feedback on their looks, performance, and acting. Trying to silence this kind of feedback make it anti-consumer. This isn't social media; it's a porn site, and models are judged based on their appearance and performance.