In August 2021, reports surfaced concerning an on-set injury sustained by Letitia Wright during the filming of Black Panther: Wakanda Forever.
Though the full extent, nature and circumstances aren't known, the injuries are said to be minor, and Wright's representatives have since confirmed their client has been "recovering in London since September." According to another THR report, Ryan Coogler (director) has spent the past 2-3 months filming as much Shuri-free Black Panther 2 streaming gratis footage as possible, but now finds himself unable to proceed without Letitia Wright's involvement.
As per her official statement, Wright won't be returning to Black Panther 2 until "early 2022," which effectively means the MCU sequel has entered production shutdown for at least 2 months.
Though there certainly could've been other factors involved (reshoots and COVID procedures lengthening filming, for example), it's possible Black Panther 2's production shutdown contributed to the recent spate of MCU movie delays. October 2021 saw a mass reshuffle of the Phase 4 slate, which Kevin Feige vaguely attributed to "production shifts and changes." By this point,
Letitia Wright was already recovering in London, and Ryan Coogler would've been rapidly running out of material to shoot without Shuri. Highlighting the big drawback of a shared universe, if Black Panther 2 suddenly needed additional production time, the entire Phase 4 slate could've potentially been affected, though this isn't something Marvel Studios has officially confirmed.
COVID-19 is still very much changing how the world operates, and in order to avoid lockdowns, restrictions and isolating employees, many workplaces are encouraging the vaccine to reduce infections and limit the virus' severity. More than simply encouraging, vaccine mandates and vaccine passports are becoming increasingly common across the globe.
Many mass gatherings and sporting events require proof of vaccination to attend, and Joe Biden's administration is currently working toward mandatory vaccination for healthcare workers - something the UK is also implementing. As well as healthcare and entertainment, vaccination is a key requirement for the travel industry too, and this is where Black Panther: Wakanda Forever could encounter another Letitia Wright problem.
Current travel rules demand non-US citizens be vaccinated before entering the country
That guidance only came into effect November 8, and will likely remain in place for the foreseeable future. Letitia Wright is confirmed by her representatives as presently residing in London, and the actress does not hold US citizenship. Assuming Wright is not vaccinated (and if her YouTube viewing habits are anything to go by, she most likely isn't), she would not meet the requirements for travelling to the US and filming Black Panther: Wakanda Forever in Atlanta.
Should these travel arrangements remain effective come early 2022 (when Letitia Wright is expected to return after her injury), a tricky scenario could arise whereby the actress either gets vaccinated and flies to the US, or Black Panther 2 faces further delays due to Wright's unavailability.