I don't agree with 2. If you look at any great work of art in movies or videogames it's easy to pin-point to one or just a few people that heavily influenced specific creative aspects of the final product. For a character to be memorable enough that a corporation decides to invest to make it a flagship one, you can rest assured there will be some great mind behind it that influenced it heavily to make it stand out in the crowd.

If you were to take an committee of execs/businesspeople and make them create the "perfect MCU character" it would be either a copycat of something existing, or something so bland and safe that fans would forget in one second. That's why they still hire screenwriters and directors.

I would also argue that tasking a team of creatives of coming up with a brand new superhero that: 1) fits the "MCU style" 2) it's safe and family friendly 3) is original enough to stand out 4) is likable 5) fits the current zeitgeist without feeling like a PR stunt. - would be an extremely daunting task for even the most experienced creative team. They might manage to do it and create a new flagship character for the MCU owned entirely by Disney, but it wouldn't be a "corporate character" and the real authors' influences and creativity would be extremely apparent in the character.