I'm convinced it has to do with the increased importance of the overseas markets, these movies now must make it past Chinese censors and make sense for people that don't natively speak English or understands its nuances. Showing a flashback scene and swapping in the government approved voice over is a better business decision than not releasing the movie in insert country here.
Unrelated movie trailer https://www.youtube.com/watch?v=kRqxyqjpOHs
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