I believe that’s the correct interpretation of Hugh Everett’s “Many Worlds” hypothesis. There are a number of different notions of a multiverse, but Everett’s “many worlds” is the formulation usually used to account for quantum superposition. AIUI, the error in the OP is assuming that collapse of the Schrodinger wave function somehow “creates” alternate universes. It doesn’t; instead, what we see as wave function “collapse” is every possible quantum state settling into its own pre-existing universe. Or, IOW, what @LSLGuy said.
I’m certainly no expert, but there was a good set of articles in the 5 July 2007 issue of Nature (Vol 448, Issue 7149) on the 50th anniversary of the publication of Everett’s “many worlds”. hypothesis. To quote David Deutsch from one of those articles, “our Universe is only a tiny facet of a larger multiverse, a highly structured object that contains many universes. Everything in our Universe — including you and me, every atom and every galaxy — has counterparts in these other universes.”
Deutsch has long been a firm believer in “many worlds”. Famously but controversially, he was one of the first to propose quantum computers, not so much as computing engines per se, but in his view as an empirical demonstration of the ability to harness massive amounts of computing power from not just one universe, but from many. Here’s an interesting quote from his book The Fabric of Reality:
To those who still cling to a single-universe world-view, I issue this challenge: explain how Shor’s algorithm works. I do not merely mean predict that it will work, which is merely a matter of solving a few uncontroversial equations. I mean provide an explanation. When Shor’s algorithm has factorized a number, using 10500 or so times the computational resources than can be seen to be present, where was the number factorized? There are only about 1080 atoms in the entire visible universe, an utterly minuscule number compared with 10500. So if the visible universe were the extent of physical reality, physical reality would not even remotely contain the resources required to factorize such a large number. Who did factorize it, then? How, and where, was the computation performed?