Depends how you interpret it. If you say a new universe is created with every quantum decision, then you could argue that(though I’ve always treated conservation laws as being descriptive, not proscriptive—there’s no operation which changes the net amount of mass-energy, so it’s conserved, but that’s not a philosophical requirement). But the treatment of many-worlds I see more commonly is that there’s already an infinite number of worlds, and it’s merely a newly-distinct world that is created with a quantum decision.
Depends how you interpret it. If you say a new universe is created with every quantum decision, then you could argue that(though I’ve always treated conservation laws as being descriptive, not proscriptive—there’s no operation which changes the net amount of mass-energy, so it’s conserved, but that’s not a philosophical requirement). But the treatment of many-worlds I see more commonly is that there’s already an infinite number of worlds, and it’s merely a newly-distinct world that is created with a quantum decision.