You've just mentioned the #1 thing fans in this thread are afraid of, that she'll be (or start out) as the antagonist. However it doesn't seem all that likely, especially when they still have so few superpowered women in the MCU (though who knows, I've seen people who are very sensitive to misogyny in portrayals of other characters who think it would be totally cool to see Wanda go baby-crazy in the MCU).
But in any case 2021 will be a bigger year for the character than they probably thought it would be a few months ago and now they really don't know what the MCU future is for her, where before it just seemed like she would either settle down with Vision, fracture reality to be with him, or both.