The Marvel Cinematic Universe proved 12 years ago that it could deal with a common concern regarding Phase 5 and the recent introduction of several powerful characters into the franchise. The MCU has dealt with balancing the powers of its heroes – and questions as to whether it would be able to continue doing so – more or less since its inception. This is in part because figures like Iron Man and Captain America can be some of Marvel's strongest comic combatants, depending on the storyline in question.
