No, we see the point you're trying to illustrate, certainly. I don't think it's possible to argue that it doesn't happen. At the same time though, it does require a lot of speculation and it also means that Jane is taking things said IC to be OOC attacks. Of course, the line is often blurred between OOC and IC but if 'Sally' assumed that 'Jane' was doing that then isn't the correct answer to speak to the player about it? Communication, when it comes to RP, is so important and it's often miscommunication and assumptions that lead people to believe they're being mistreated or bullied in the first place.
I don't know. To me, bleeding IC/OOC is bleeding IC/OOC and speculating that someone is attacking you just because you don't like them or you assume they don't like you is often times just as bad. Especially if it leads to 'Jane' using rpvents and similar communities to complain about the way she's being treated when, in all honesty, Sally might have seen it as an IC thing for the conflict to occur. (Like, sure, maybe Bob asked Frank to leave him alone, but maybe Frank wouldn't. That's all IC. It would be an entirely different story if Jane were to OOC ask Sally to leave her alone, I would think. It isn't fair to assume that a character's player gets your OOC intention, really.)
Additionally, RP is a game and that should be remembered. I think it's unfair to compare RP comments (and speculating about them) with things like Facebook 'hate' communities, or horrible comments and insults circulating on someone's personal blog, youtube account or anything else, all of which have lead people to do terrible things to themselves and others. I also think that, if someone feels particularly pressured or abused in a game or by certain players, they have choice and opportunities to take it to moderators or to just step away from the game but in real life, those options don't really exist.