Completely disagree.
I think Lois Lane is one of the most complicated female characters to play. Because she's kind of a little bit of everything all carefully balanced into one. She's a bit of b****, she's spontaneous, impulsive, take no prisoners, all out for number one, competative. She's also kind, passionate, with a strong sense of personal morality and disdain towards injustice. And she is intelligent, witty, sarcastic, tongue in cheek. And she is both feminine and sexy when she needs to be. And she's secretly emotionally vulnerable.
But how easy a role is to play entirely depends on how much importance the character is given within the film.
If Goyer/Snyder attempt to capture the majority of the Lois I just described, without taking up all the screen time with her characterisation, it will be a very difficult role.
If they don't bother trying to capture much of that, and just have her be a one dimensional love interest, then sure, it'll be easy.