See here: https://80000hours.org/podcast/episodes/david-wallace-many-worlds-theory-of-quantum-mechanics/
Basically, you can treat fraction of worlds as equivalent to probability, so there is little apparent need to change anything if MWI turns out to be true.
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See here: https://80000hours.org/podcast/episodes/david-wallace-many-worlds-theory-of-quantum-mechanics/
Basically, you can treat fraction of worlds as equivalent to probability, so there is little apparent need to change anything if MWI turns out to be true.