If I may mix in my three pennies:
One- there are other sins to be aware of, besides of Lashon Hara, namely onaas darar, hurting another through words. Includes any pain, anguish, discomfort etc. one causes another through communication.
Two, as mod?? pointed out earlier, a lot of posters know each other. Some lurkers also know posters. (I’ve received many phone calls about stuff that goes on here. And now I’m gonna get another…)
Three, people are somewhat connected to things they write, or to their s/n. Saying something like “Little Froggie, you’re a dunce” is quite likely to cause me slight discomfort.
Four, let me take this opportunity to thank the Mods. They are doing a FANTASTIC job of modding, filtering and keeping this place safe for a Frum person to spend some time. I’ve had the user end of their modding staff too (actually many times)… still they’re doing a most wonderful job, and if I recall they’re doing it without any monetary compensation. So again I LOUDLY applaud the tireless Mods!!!