Ant-Man and the Wasp: Quantumania producer Stephen Broussard explains how MCU actors like Paul Rudd and Jonathan Majors are able to advocate for their characters across projects. Actors take on characters in the Marvel Cinematic Universe for years across multiple projects with a variety of directors. It makes sense that actors like Rudd, who has played Ant-Man since 2015, and Majors, who has already played two different Kang variants, would be the most consistent voices for their characters. Marvel Studios actively working with them to collaborate on these characters' development makes the evolution feel more natural with a consistent character across stories.
https://screenrant.com/ant-man-kang-paul-rudd-johnathan-majors-input/