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Does it not make any predictions? It states there is no such thing as wavefunction collapse. This means that if you entangle a state with a large system, in theory you could ‘disentangle’ it. Of course, this is no easy feat. But indeed quantum computing to me, is an example of this feat. We can entangle systems on a large scale, then use this feat to make calculations. Inspiration for quantum computing actually came from many worlds.

Many worlds is falsifiable, if you can show wave function collapse actually happens (not just decoherence). I believe that in the not so distant future we will get more and more proof that wave function collapse never happens. Quantum computing at scale to me is an indication that Everett was just right..

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This is the way! It is absolutely amazing that the supposedly "brilliant brains" at lesswrong and other similar outfits, have not learned about the difference between an interpretation and a theory.

Since QM goes beyond our material world intuitions, I am personally loathe to clothe nrs in words, until we have more and better experiments. I think prematurely translating it into material-level intuitions just leads to a waste of time and much confusion.

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(Disclaimer: I'm nowhere near truly knowledgeable about any of this)

Quantum computing was explicitly proposed as a way to prove the truth of many worlds. As far as we can tell, quantum computing appears to work.

I don't think most people believe QC truly proves many-worlds, but I think it is considered some evidence in its favor, and historically it was I think one of the reasons for the development of QC originally.

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I've heard this claim, but I don't think it holds up. The idea is that supposedly the calculation is done in parallel across the different universes which allows you to see an exponential speedup in some calculations. But the whole point of many-worlds is that after a branch event the various branched portions of the wavefunction no longer interact. Even if it were true that quantum computing was really a bunch of parallel classical computations (which it is not), there would be no way for any of the other universes to communicate the result back to the universe you observe it in.
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Many worlds doesn't really feature 'hard branches'. In fact the interpretation is pretty specific that quantum interactions becoming de-correlated and stopping to react is the mechanism by which you get the 'many worlds', and this is a soft and messy process not some global hard split.

OTOH, I don't think any of the other interpretations really struggle to explain quantum computing so I agree it's not much of a distinguishing factor.

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I don't think there is anything in quantum computing that is specific yo the many worlds interpretation.
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But if what you want is understanding, you want a good explanation. (Or to quote TheOtherHobbes from elsewhere in these comments, a reasonable metaphor: https://news.ycombinator.com/item?id=50220700)

If you only like predictions and disparage explanations, I might start calling you names, specifically instrumentalist.

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What do call someone who wants good "Just So" story explanations that don't explain anything, but posit the existence of meaningless things?
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Here you are taking "good explanation" and combining it with the term "just so story" which indicates a bad (arbitrary) explanation. So you cast doubt on the idea that explanations can be good. What's this, sabotage?
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It has mathematical and philosophical content. People can be convinced for reasons other than empirical without it being emotional. Sean Carroll makes logical arguments for why he's convinced MWI is correct.
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I'm not Sean Carroll. I'm interested in logical arguments for why I should be convinced that something completely impossible to ever test, not even in theory, is correct.
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How do you test whether the dinosaurs once existed as living animals, vs as fossils that were embedded in the Earth when the universe began 6000 years ago?

Because I only believe one of these propositions, even though I can't imagine any test that would discriminate between the two.

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