I don't know that I've ever seen anyone say that both sides are the same. I have seen people (when talking about the US) call out when both sides do the same things, such as: Put forth rapists and child-killers as candidates, back a genocide, send people to torture prisons, refuse to fix the healthcare system, etc.
B is indeed worse than A, but I've seen too many people use that to pretend that one side is "actually good", instead of being able to see that both sides are bad.