Another problem, which has always been a stumbling block for me, is the source of all these new universes. Every second, billions of universes are being created. (Do I stop for gas or don't I? Do I make that phone call or don't I?) Aside from the problem or the origin of all this stuff, where does it all get positioned? If it exists, it's part of our universe. If it's another universe entirely, where is it? And why does the activity of humans have this amazing creative power?
It doesn't. Human decisions are easy to visualize and convenient to state for the sake of argument, but they are chicken feed compared to the 20 or so orders of magnitude of quantum transitions that occur in every gram of matter every fraction of a second. Each one of those creates worlds, too, in this interpretation.