Satoshi is gone for good. If he wanted to cash out, he'd have cashed out already. If he wanted to reassure the world that those coins are gone, he'd burn them by moving them to some known black hole address.
Nooooooo! Satoshi would not spam the UTXO set.
PSA: Never use burn addresses! They are bad for Bitcoin, bad for nodes, bad for scalability. If you want to destroy bitcoins, place them in the amount field of an
OP_RETURN output. That is unspendable, according to consensus rules; thus, the output is pruned from the UTXO set. Auditors of Bitcoin’s supply typically also subtract
OP_RETURN amounts from Bitcoin’s supply cap.
The UTXO set size is one of Bitcoin’s biggest scalability issues
(so to speak). Please don’t make it worse by polluting the UTXO set with bloat that nodes will need to track forever and forever. Be environmentally responsible!
See how
I irrevocably destroyed one satoshi in a sane and responsible way (
txid 000000000fdf0c61...).
Satoshi is gone for good. If he wanted to cash out, he'd have cashed out already. If he wanted to reassure the world that those coins are gone, he'd burn them by moving them to some known black hole address. The fact that the coins are still there after all that happened with bitcoin and finance and multiteradollar marketcap can have two explanations:
1 - Satoshi is gone for good
2 - Satoshi likes to keep bitcoiners on their toes
I lean towards 1.
Third option: Satoshi is in jail.
Fourth option: He lost his keys. But perhaps the keys may not be unrecoverable. There are other cases of people who had crashed hard disks or whatnot, who later recovered their coins after some effort and expense. In Satoshi’s case, he probably would not want to risk hiring professional services to help him; thus, it would be even more difficult for him.
Fifth option: Satoshi is drugged and tortured in a CIA black site, because the US is cancer and they play dirty.
Sixth option:
Satoshi is alive, well, and at liberty. He is also smarter and more realistic than all of the people talking monkeys who speculate about him. He realizes that
nobody knows how many coins he has—the “Satoshi has a million bitcoins!” meme is just that, merely a meme, a rumour based on vexed and unreliable evidence.
Why would he move his coins? Especially, why would he move all of his coins at once, which would effectually flag the coins as “probably Satoshi’s”? And most of all, why the hell would he “cash out” when 1 BTC = 1 BTC?

(It should go without saying, he is probably not dumb enough to burn his coins “to reassure the world” or whatever. WTF? The coins are his. He damn well earned them.)
For all you know, Satoshi
is moving his coins. Bit by bit. Moving the balances of a few Satoshi-mined addresses per year (or whatever) into circulation, at random times.
Or he may simply be HoDLing. Why fix what ain’t broken?
It’s not like we have an exact list of Satoshi’s addresses. For all we know, he already cashed out like 1 million and he’s just living off of that and biding time for whatever his grand plan is.
That’s what I would do, if I were Satoshi.
Heirs. Think long-term. Is Satoshi a long-term thinker? Only foolish commoners fail to put dynastic considerations
first. Perhaps the Nakamoto Dynasty is being founded with quite
a royal treasury an Imperial Treasury.