WARNING: Doctor Strange In The Multiverse Of Madness.
The MCU needs more stories like the Scarlet Witch in Doctor Strange In The Multiverse Of Madness to survive Phase 5. The Doctor Strange sequel takes the character to a dark place, much darker than any story she's had before. While this change has caused division and criticism among some viewers (much like the rest of Phase 4), it is still a bold move that could have a positive effect going forward. Notably, it could be what the MCU needs to remain sustainable past Phase 5.
Wanda Maximoff's arc in the MCU is rife with tragedy. After spending most of the franchise as an Avenger following her villain role in Avengers: Age of Ultron, Wanda still faces contention through accidentally causing a massive explosion in Lagos as well as losing both her brother and her lover. In Doctor Strange In The Multiverse of Madness, through corruption from the MCU's Darkhold as well her obsession with regaining the children she lost in WandaVision, she embraces her role as the Scarlet Witch and becomes a full-fledged villain in the process. While this is an upsetting turn for the character to take, it's also one that the MCU hasn't tackled before.
While the MCU has dealt with morally complex storytelling before through films such as Captain America: Civil War, Wanda's story is different. In essence, her arc in Doctor Strange In The Multiverse Of Madness is the perfect example of a failed redemption arc, which is something the MCU has never tried until now. For the most part, a majority of the conflicts in the franchise have been largely black-and-white. With Scarlet Witch's change from hero to villain, a new shade of grey is added that opens the door for different kinds of stories in the MCU. Likewise, now that Scarlet Witch is possibly dead in the MCU, at least the villainous version of the character, there is likely no path to redemption.
How The MCU Can Stay Fresh Through Phase 5
The MCU's Phase 4 has been incredibly experimental in its approach to new projects. While not every project has been completely well-received, it still allows the franchise to reinvent itself post-Infinity Saga and explore different genres and narratives moving forward. Scarlet Witch's arc in Doctor Strange In The Multiverse of Madness is the MCU asking what would happen if it took a former villain and had them revert to their old ways. While it certainly may make viewers (especially fans of said character) uncomfortable, this type of character arc deepens the storytelling of the MCU and will be what it needs to remain fresh once Phase 5 comes around.
Now, it's still possible that the Scarlet Witch's MCU future holds redemption should she ever return. For now, though, tackling a failed redemption arc in Doctor Strange In The Multiverse Of Madness is a big step forward for the MCU. Given that the franchise is now at risk of running out of steam, the time is now to try out these new story beats and see what works. With that in mind, the MCU could be substantially different in the future, but that's not a bad thing.