Do you know how long I've waited for Spectrum to come to the big screen? Or even Blue Marvel? There was nothing wrong with the portrayal of Monica. She wasn't what was wrong with the movie.
Like I said before, most people didn't watch WandaVision... And if they did, they don't remember her from the show. Spectrum, Blue Marvel ( and their romance), the Shi'ar, Squadron Supreme, Brother Voodoo, Etc... I've wanted to see them ALL on film. I want to see Peter meet Wolverine. I want to see Monica team up with Storm... I want to see Eric team up with Kang or Namor.
But the movie didn't fail because of what you said in your post. I explained why I think it did and I think my thoughts on it are closer to the truth than "woke" or "annoying women" or "fangirl teen".