Satoshi didn't conceptualize the idea of it, he basically combined the various ideas; b-money, distributed ledgers, etc into Bitcoin AND made it work. I have no doubt that even without Bitcoin, Blockchain would've appeared sooner or later but without all the hype. Blockchain is mostly just a snakeoil. Corporations love to use it with their sentences, makes them sound cool and brings some nice PR.
Blockchain wouldn't appear without Bitcoin. It would be nothing more than a very obscure programming pattern barely used anywhere, and the only people who know about it would be some guys from stackoverflow. It only exists as we know because of the huge marketing campaign created by altcoins and blockchain companies that tried to sell it as the next big thing.