The Marvels is certainly not one of the strongest MCU films, but by far not the worst. The fact that the film is still performing so disastrously is most likely due to oversaturation and weak marketing compared to other films.
Nevertheless, the film seems lost in the larger MCU context. It is not explained why Fury is suddenly traveling with a new organization in space. Additionally, viewers are left bewildered with the introduction of the X-Men at the end.
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