> in line with the idea that we live in a multiverse, a prediction first made by David Deutsch.

I think Hugh Everett beat him to it:

https://en.wikipedia.org/wiki/Hugh_Everett_III

https://en.wikipedia.org/wiki/Many-worlds_interpretation

Wheeler and Everett being over 60 years ago this can't be called especially ground breaking. The interesting question would be how information might flow.

"Must have" is begging the question. Really, Google staffers emoting adds nothing.

"Lends credence" is more plausible. It's consistent.

This still feels like a purpose specific problem solver not a general purpose computer. Steps along a road.

> Google says its new quantum chip indicates that multiple universes exist

So is the Schrödiger's cat alive or dead in those universes ?

you might as well say that it proves time-travel is possible. https://en.wikipedia.org/wiki/Two-state_vector_formalism