Or why is mwi impossible to verify.
[1] There is this one theory whose name I cannot remember, where each particle in the universe gets their wavefunction multiplied by a delta function or very thin gaussian at random intervals, and whose sudden localization also causes a sort of chain reaction and localizes all particles it is entangled with. This theory is interesting because it helps set a (statistical) limit between microscopic and macroscopic interactions; basically, when you go past a certain number of entangled particles, everything will be well-localized virtually all of the time, but for small numbers of particles we'll see quantum phenomena. Unfortunately I recall this theory having too many holes, and perhaps it has already been falsified, but the point is that at least it made an effort to address inherent problems in QM (namely, wavefunction collapse) in a way that physicists actually should; by making testable claims.
The characterization is a little bit harsh, but yes. The Copenhagen interpretation is non-falsifiable, (relative to MWI) so while I don't know what it is, I know it isn't science.
There's a reason most reputable scientific journals don't accept papers dealing with interpretations of quantum mechanics. There's no "there" there.
Hawking radiation is interesting because a proof of lack of Hawking radiation is a proof of the falsehood of quantum mechanics. Which is really interesting; any time you can falsify something like quantum mechanics every physicist should be paying attention. Also, if certain models of string theory are correct, particle accelerators like the LHC should be able to produce micro black holes, which will then evaporate in detectable ways. So Hawking radiation is of observational interest as of 2010 as a possible way to provide evidence to support string theory. (spoiler alert: we didn't find any)