A lot of actors in the MCU have become iconic now to the worldwide audience thanks to their respective roles in the franchise and it's hard to imagine at this point to see other actors' take on those beloved characters.
One of the castings in the MCU that fans have lovingly responded to is the late Chadwick Boseman's performance as T'Challa/Black Panther, which instantly became beloved when he debuted in Captain America: Civil War and became iconic in the first Black Panther film.
Other stars in the MCU such as Chris Evans who is now associated with Captain America, a then-unknown Chris Hemsworth is now recognizable worldwide thanks to Thor, Karen Gillan has become well-known now for her role as Nebula, and many more countless examples that we can think of.
Chadwick Boseman and Lupita Nyong'o Auditioned for Guardians of the Galaxy
In an excerpt from the new book MCU: The Reign of Marvel Studios that was released by Vanity Fair, an interview with casting director Sarah Halley Finn revealed some of the intriguing alternative castings on the iconic MCU roles that are now beloved by fans
Finn shared that she saw Boseman's audition for Drax in Guardians of the Galaxy (which obviously went to Dave Bautista). The actor's Black Panther co-star Nyong'o also auditioned for Gamora, which ended up going to Zoe Saldaña.
Another interesting casting that happened during the earlier years of the MCU is when Gillan was originally auditioning to play Sharon Carter in Captain America: The Winter Soldier which ended up going to Emily VanCamp.
Fortunately, Finn saw the Doctor Who actress as a perfect fit for Nebula because of her "cherubic look even when she was projecting menace" and, as we know now, she nabbed that role.
More "casting what ifs" that were highlighted in the book are Succession star Alexander Skarsgard as Thor and John Krasinski as Captain America, who eventually joined the MCU to cameo as Earth-838's Reed Richards in Doctor Strange in the Multiverse of Madness.
This is a very interesting piece of information that fans will definitely think about since it just shows us that the MCU that we know today could have been so different if Finn and the team at Marvel Studios made another choice instead with their casting.
It's also a great example of how crucial the casting process is and how gratifying it is in retrospect as things went well by the end despite the apprehension that they might have back when it was happening.