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The theory is appealing to many because it avoids non-determinism. It's unappealing because it's strictly more complicated than the interpretations that don't have this extra object, but predicts nothing beyond them. By Occam's razor it's not as good as the simpler interpretations.
I'm not a physicist, but doesn't classical QM have the problem of the "collapse of the wave function", i.e. "suddenly" Schrödinger's equation does not hold anymore - a problem that the De Broglie-Bohm theory does not have? Shouldn't this be considered as a strong sign against "typical" QM formulations and for the De Broglie-Bohm theory?
The wavefunction collapse is messy and awkward. It's taken as an axiom, basically, in the Copenhagen interpretation. It's not as awkward as introducing another equation and set of rules to skirt around it, as Bohmian mechanics does, in my opinion.
Many-worlds - which starts with being a lot more rigorous about what 'measurement' is (entangled yourself with the system in question) is much simpler than either, I think.
My general impression is that Many-Worlds is getting more popular as physicists make precise how entanglement, measurement, and decoherence exactly work. I think it'll supplant Copenhagen as what we teach in intro classes eventually. But this is just my impression from the physics blogs and papers I've read; I'm not a physicist myself.
Classical QM (Copenhagen, if I'm not mistaken) does have that problem. The collapse is indeed an additional hypothesis done on the part of the wavefunction the math already says we cannot observe. As always, unfalsifiable additional hypotheses are bad.
I can't speak for De Broglie-Bohm, but it would seem that theory also have a similar strike against it: the math is more complex than the equations QM physicists are familiar with. It's just not the simplest theory that fits the observation.
The obvious alternative is to just stick to the math. Problem is, the simplest math that explains our observations implies a universe that forks all the time. For some reason, possibly the intuition of a unique universe, many people cannot accept that.
I'm not a physicist, but doesn't classical QM have the problem of the "collapse of the wave function", i.e. "suddenly" Schrödinger's equation does not hold anymore - a problem that the De Broglie-Bohm theory does not have? Shouldn't this be considered as a strong sign against "typical" QM formulations and for the De Broglie-Bohm theory?