IMO the Article is AKA ~~~ Characters that have Struggles that they have to work on threw mulitple Movies are Not Villians, They are like most other MCU Protagonists, They are the HEROES!
When we think of the MCU, most of its villians have been mostly absolutes with little struggle in who they are outside of Loki or Thanos. Yet they where still mostly absolute in their views of themsevles and their actions with most points, baring showing any idea of true struggles in their chooses or life.
So a Character that is working on their own weaknesses and darkness with most heroes all have it usally that of a character working to a Hero and that is my View of what this article was getting at IMO.
Tony Stark had to struggle with the guilt of his weapons and then his PTSD with his worry of how to Protect the World. Steve Rogers had this man out of time struggles with all he cared about mostly old and gone with wondering if his views on things could work in the future like we saw in The Winter Soldier and Civil War. Black Widow all the time had to deal with her past of being a Red Room Assassin.
Bruce Banner with being the Hulk and the dual persinalities, Thor with his place in Asguard and how his action effected his people. Star Lord with his parent troubles, the GotG learning to get along with each other, Scott Lang with his parenting and place in society.
It can go much on, each hero has had struggles that feel real and geniune to the audiances, it is a human quality that IMO what has made the journey threw the MCU and what made Marvel Comics truly stand out as it has.
Heck, Coming Up in the next Disney+ Show, In Falcon and the Winter Soldier, their struggles will be mostly against getting along with each other, the Odd Couple complex and how that effects the world around them and the people they care about.