I think it is important that people learn the difference between assur and siyag latoirah… I find that a lot of acual halacha gets crossed over because we are not taught the difference always of whats precaution and what is real. When a girl is told its assur to speak to a boy and then she comes in a situation where she has to, either it can make things very difficult or it can have the opposite affect, once she crossed over that line and it didnt seem so bad then maybe some of the other mamish assur things aint that bad either. unfortunately I have seen this scenario too many times. From boys and girls. There must be separation because of tznius, as a preventative to worse things.
As for the YWN aspect… it taka can be an issue if people step overboard. I wouldn’t rate it as forming a relationship like an IM because we really dont give identities and genders (except some) but a group conversation to accomplish a thought or a point is basically all that is meant to be on this.
If you feel that it is lowering your ruchniyus standards and you are crossing the line, by all means, please refrain from participating in conversation. And if you feel someone else is… maybe give a loving warning or alert our dearest mods and eds. 🙂