There is still a lot of hate against Seven (right this morning I read the nice nickname someone gave her: Borg bitch) and I still do not know why
Part of it might be the "why" of the character came on the show - this was the thing hardest for me to get over (and while I mostly am, if I think about it too
hard I get a bit mad,) and I think another is 'shipping
J/Cers have a tendency to be hostile to Seven, J/7ers have a tendency to be hostile to Chakotay, and C/7ers tend to be hostile to Janeway. It's not exactly true across the board, of course, but that's how it seems. Ah, the Love Triangle.
Whatever character is the third wheel in the 'ship is considered competition and needs to be eliminated.