Let's say in this thought experiment that he released a PGP signed message that proves he's indeed Satoshi. The way I see this playing out is...
The crypto world starts kissing his ass. People start wondering what political party he aligns with (assuming he's American). Karens start calling him selfish for not donating some of his million plus BTC to charity. VCs ask him to invest his Bitcoin Cash. They'll probably tell him something like, "that's money you didn't even know existed since you just came out of a coma, and it won't even affect your BTC, Satoshi."
This might be the start of the next bull run.
Or an even bigger crash as Satoshi sees how much the world has gone to shit and sells all his crypto, further bringing down the price and the entire altcoin market down with it.
Then takes the fiat and burns it like Heath Ledger's Joker did.
