Having just read the OP so far, I would say this: in online matters where we're discussing the functions themselves, I think we feel like it's more a matter of being understood. In real life, we'd work a little harder to figure out where the other is coming from, but here, we're thinking about how we most naturally react. They are preferences after all, and wouldn't we usually prefer to react in ways that make the most effortless sense to us? So maybe deep down, in these discussions, we're hoping that it might make as much sense to others, once they know where we're really coming from.
In those Fe/Fi discussions, I always feel like I mostly relate to the Fe side, and there are others who much more naturally relate to Fi. It seems like it's more useful to be able to see what each side looks like if it were able to run rampant instead of compromising, than it would for each poster to say what it thinks the other side wants to hear. After all, when do we ever get to do that in real life? I think an unfettered look at each approach is much more useful in understanding how each function approaches a situation. So, yeah, I think it's much more pronounced here than it would be if we interacted with each other in a normal social or work setting.