I don't recall either CE or HA ever confusing Sharon's character with EVC, though. And there were plenty of valid reasons to be squicked by how Sharon and Steve's relationship was portrayed on screen, but that's on the creators that chose that route for the characters. 'Shipping' isn't why fans are inappropriate or mean to an actor/actress, it's just the excuse. But because 'shipping' gets the easy blame, we never address the real issues, which often come down to misogyny, homophobia, hetero-normative bias... etc.
eta: There's also a HUGE difference between explaining why you find something (popular or not) problematic, and specifically telling someone they're wrong for liking/disliking something, or dismissing/belittling their reasoning either way. And that fundamental misunderstanding of what helps foster effective discussion/communication is found everywhere, not just 'shipping wars'.