The simple answer is that it's worth something until it's not. So the sats I've got in a custodial lightning wallet that I exchange for a steam key on Joltfun are worth something because I was able to use the sats in exchange for a good1.
Similarly, if I've got BTC on an exchange and send them to someone's wallet in exchange for a good, that's still worth. As would be selling the BTC on the exchange for fiat (stupid, but there's an explicit value of sorts).
Of course, these both rely on trusting other entities, and as you note, that "worth" can go away at any time. And if you modified your question to "long-term worth," I think the answer becomes closer to a definitive "no."
I do feel that ETFs and Exchange BTCs are different beasts, though. Folks using ETFs are simply treating Bitcoin like any other investment like a stock or bond, and only care about how much it's worth in fiat. Folks with BTC on the exchanges might be doing this, but might also think they'll take the BTC into a wallet some day, or exchange it for something other than fiat.

Footnotes

  1. Yes there's a legit secondary question about Steam keys being goods we "own."
Good point about the difference between exchange BTC and ETF vouchers.
Let's think about sats on SN. None of us have our keys here. But we can withdraw at any time and so until that changes, we treat SN sats like real sats.
When using external wallets on SN gets built (note my effortless confidence in the SN devs) we will all be using Lightning and so no problem.
But what if external wallets turns out to be more trouble (expensive) than it's worth for the SN use case?
What if an ecash mint makes more sense? In that case, would it be different than using a database (which is what I assume SN does now)? That difference us what curious about.
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44 sats \ 4 replies \ @ek 26 Mar
When using external wallets on SN gets built
You can already attach external wallets via NWC. The UX does not match the custodial UX as much as we'd like yet (it's one of our priorities right now) but it's something that's already possible.
Not sure if you already knew, your comment didn't sound like it.
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Haven't used nwc much. Does this mean balance gets held on the external wallet and zaps come from there?
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61 sats \ 2 replies \ @ek 26 Mar
Yes, I use this from @benthecarman
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That's pretty cool! I thought we were still just at auto withdraw above a threshold and that's it. Man, you guys are awesome!
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27 sats \ 0 replies \ @ek 26 Mar
Man, you guys are awesome!
Thanks :)
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